RISK FACTORS

         You should carefully review and consider the following risk factors and the other information contained in this proxy statement/prospectus, including the financial statements and notes to the financial statements included herein, in evaluating the business combination and the proposals to be voted on at the general meeting. The following risk factors apply to the business and operations of Envigo and will also apply to the business and operations of ENVG following the completion of the business combination. The occurrence of one or more of the events or circumstances described in these risk factors, alone or in combination with other events or circumstances, may adversely affect the ability to complete or realize the anticipated benefits of the business combination, and may have a material adverse effect on the business, cash flows, financial condition and results of operations of ENVG. You should carefully consider the following risk factors in addition to the other information included in this proxy statement/prospectus, including matters addressed in the section entitled "Cautionary Note Regarding Forward-Looking Statements." ENVG may face additional risks and uncertainties that are not presently known to us, or that we currently deem immaterial, which may also impair ENVG's business or financial condition. The following discussion should be read in conjunction with the financial statements and notes to the financial statements included herein.

Risks Related to Envigo and its business

Changes in government regulation or in practices relating to the biopharmaceutical industry or the contract research industry could decrease the need for the services Envigo provides or result in increased costs for Envigo.

        Governmental agencies throughout the world strictly regulate the drug development process. Envigo's business involves, among other things, helping biopharmaceutical companies navigate the drug approval process. Changes in regulation, such as a relaxation in regulatory requirements or the introduction of simplified drug approval procedures, or an increase in regulatory requirements that Envigo has difficulty satisfying or that make its services less competitive, could substantially reduce the demand for Envigo's services. In addition, if new legislation were to mandate a significant reduction in safety testing procedures which utilize laboratory animals (as has been advocated by certain groups, including petitions by anti-vivisection groups for the European Union ("EU") to ban all animal experimentation) Envigo's business could be materially adversely affected. Also, if the government were to introduce measures to contain drug costs (as has been advocated by the United States' current administration) or biopharmaceutical company profits from new drugs, Envigo's customers may spend less, or reduce their growth in spending on research and development.

        For example, in the United States in March 2010, the US Congress enacted The Patient Protection and Affordable Care Act, health care reform legislation intended to expand, over time, health insurance coverage and impose health industry cost containment measures. This legislation may significantly impact the biopharmaceutical industry. Regulations under that Act were promulgated in 2013 and approximately 20 million people have enrolled under that law. Efforts to repeal that law have been introduced in Congress and undertaken in the courts. The current U.S. administration has announced a desire to repeal and replace this law and Congress has made efforts to do so thus far without success. It is not possible to predict whether and when any such repeal or change will occur. In addition, the US Congress, various state legislatures and European and Asian governments may consider various types of health care reform in order to control growing health care costs. Implementation of health care reform legislation that contains costs could limit the profits that can be made from the development of new drugs. This could adversely affect research and development expenditures by biopharmaceutical companies which could in turn decrease the business opportunities available to us both in the United States and abroad. In addition, new laws or regulations may create a risk of liability, increase Envigo's costs or limit its service offerings. Envigo is unable to predict what legislative proposals will be adopted in the future, if any.

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Failure to comply with applicable governmental regulations could harm Envigo's business.

        As a company in the contract research industry, Envigo is subject to a variety of governmental regulations, particularly in the US, Europe, and the UK, relating to animal welfare and the conduct of its business, including Good Laboratory Practice regulations, the UK Animals (Scientific Procedures) Act 1986 and United States Department of Agriculture ("USDA") Animal Welfare Regulations. Envigo's laboratories are therefore subject to routine formal inspections by regulatory and supervisory authorities, including the US Food and Drug Administration ("FDA"), the USDA and the UK Home Office, as well as by representatives from client companies. Envigo is regularly inspected by governmental agencies because of the number and complexities of the studies it undertakes. Envigo must also maintain records and reports for each study for specified periods for auditing by the study sponsor and by any regulatory authorities. Failure to comply with applicable laws and regulations could result in material liabilities, the suspension of licenses, disqualification of trials, the disqualification of data collected by Envigo, the termination of ongoing research, harm to relationships with customers or harm to Envigo's reputation and prospects for future work, and could have a material adverse effect on their business, prospects or financial condition. For example, if Envigo were to fail to properly monitor compliance by its personnel with study protocols, the data collected from that study and other studies could be disqualified. If this were to happen, Envigo could be contractually required to repeat the study or studies at no further cost to the customer, but at potentially substantial cost to Envigo, or could be exposed to a lawsuit seeking substantial monetary damages. If Envigo's operations are found to violate any applicable law or governmental regulation, it might be subject to civil and criminal penalties, damages and fines and other penalties. Any action against Envigo for violation of applicable laws, even if Envigo successfully defends against it, could cause Envigo to incur significant legal expenses, divert its management's attention from the operation of its business and damage its reputation. In addition, applicable laws and regulations could significantly restrict Envigo's ability to expand its facilities or require it to acquire costly equipment or incur other material costs to comply with regulations, or otherwise increase costs.

        Envigo expends significant resources on compliance efforts. Regulations and guidance worldwide concerning the production and use of laboratory animals for research purposes continue to be updated. For example, the European Directive 2010/63/EU established new standards for animal housing and accommodations that require implementation by 2017. Similarly, guidance has been and continues to be developed for other areas that impact the biomedical research community on both a national and international basis, including transportation, import and export requirements of biological materials, and animal housing and welfare. Certain of Envigo's customers may require Envigo to comply with any new guidance in advance of its implementation as a condition to being awarded contracts. Conforming to new guidelines may result in increased costs attributable to adding or upgrading facilities, the addition of personnel to address new processes and increased administrative burden.

Envigo depends on the biopharmaceutical industry.

        Envigo's business depends greatly on the expenditures made by the biopharmaceutical industry in research and development. Accordingly, economic factors and industry trends that affect Envigo's customers in these industries also affect Envigo's business. Also, at any given time, biopharmaceutical customers can choose to allocate their research and development expenditures more heavily towards clinical testing than the non-clinical testing that Envigo performs. As well, if payers were to change their practices with respect to reimbursements for pharmaceutical products, Envigo's customers may spend less, or reduce their growth in spending on research and development.

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Several of Envigo's service and product offerings are dependent on a limited source of supply, which if interrupted could adversely affect its business.

        Envigo depends on a limited international source of supply for certain products, such as large research models. Disruptions to their continued supply may arise from health problems, export or import laws/restrictions or embargoes, international trade regulations, foreign government or economic instability, severe weather conditions, increased competition for models, disruptions to the air travel system, commercial disputes, supplier insolvency, activist intervention, or other normal-course or unanticipated events. Any disruption of supply could harm Envigo's business if it cannot address the disruption or are unable to secure an alternative or secondary supply source on comparable commercial terms.

Changes in aggregate spending, research and development budgets and outsourcing trends in the biopharmaceutical industry could adversely affect Envigo's operating results.

        Envigo's ability to continue to grow and win new business is dependent in large part upon the ability and willingness of the biopharmaceutical industry to continue to spend on compounds in the non-clinical phase of research and development and to outsource the services and products Envigo provides. Fluctuations in the expenditure amounts in each phase of the research and development budgets of these industries could have a significant effect on the demand for Envigo's services and products. Research and Development ("R&D") budgets fluctuate due to changes in available resources, mergers of biopharmaceutical companies, spending priorities, general economic conditions and institutional budgetary policies. Envigo's business could be adversely affected by any significant decrease in non-clinical research and development expenditures by biopharmaceutical companies.

        In addition to the growth in R&D budgets, the practice of many companies in the biopharmaceutical industry to hire external organizations such as Envigo to conduct non-clinical research projects has been critical to Envigo's growth. Over the past decade, the CRO industry has grown faster than the growth of R&D spending as a result of the increase in biopharmaceutical companies outsourcing their non-clinical research support activities. If they reduce their outsourcing for any reason, Envigo's operations and financial condition could be materially adversely affected. Envigo also believes that it may be negatively impacted by certain consolidation in the biopharmaceutical industry, including business reductions or failures due to a lack of financing, which could result in development pipelines being rationalized, a shift in focus from development to integration, the delay or cancellation of certain existing projects or a decrease in the number of Envigo's potential customers. If the number of Envigo's potential customers declines, existing customers may be able to negotiate price discounts or other terms for Envigo's services that are less favorable to Envigo than has historically been the case.

Envigo competes in a highly competitive market.

        The CRO and Research Models industries are highly competitive. Competition in both the biopharmaceutical and chemical market segments ranges from in-house research and development divisions of large pharmaceutical, crop protection and industrial chemical companies, that perform their own safety assessments, to contract research organizations like Envigo that provide a full range of services and products to the industries and niche suppliers focusing on specific services, geographies or industries. Some of these competitors have greater capital, technical and other resources than Envigo, while Envigo's competitors that are smaller specialized companies might compete effectively against Envigo based on price and their concentrated size and focus.

        Providers of outsourced drug development and research models and services compete on the basis of many factors, including the following:

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reputation for on-time quality performance;

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reputation for regulatory compliance;



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expertise, experience and operational stability;



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scope of service offerings;



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how well services are integrated;



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quality of facilities;



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quality and stability of the animal models;



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assurance of supply;



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technical and scientific support;



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strength in various geographic markets;



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price;



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payment terms;



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financial stability; and



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technological expertise and efficient drug development processes.

        Envigo has traditionally competed effectively in the above areas, but there can be no assurance that it will be able to continue to do so. The biopharmaceutical industry generally is subject to rapid technological changes. Envigo's competitors or others might develop technologies, services or products that are more effective or commercially attractive than Envigo's current or future technologies, services or products, or that render Envigo's technologies, services or products less competitive or obsolete. If competitors introduce superior technologies, services or products and Envigo cannot make enhancements to its offerings to remain competitive, it could be materially adversely affected.

New technologies may be developed, validated and increasingly used in biomedical research that could reduce demand for some of Envigo's services and products.

        For many years, groups within the scientific and research communities have attempted to develop models, methods and systems that would replace or supplement the use of living animals as test subjects in biomedical research. In addition, technological improvements to existing or new processes, such as imaging and biomarker technology, could result in a refinement in the number of animal research models necessary to conduct the required research. Alternative research methods could decrease the need for research models, and Envigo may not be able to develop new products effectively or in a timely manner to replace any lost sales. In addition, other companies or entities may develop research models with characteristics different than the ones that Envigo produces, and which may be viewed as more desirable by Envigo's customers.

        It is Envigo's policy to adopt and implement the 3R's of replacement, reduction and refinement, which may decrease the number of animals used in biomedical research.

Contract research and research model services create a risk of liability.

        In contracting to work on product development studies, Envigo faces a range of potential liabilities, for example:

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risks associated with Envigo's possible failure to properly care for its clients' property, such as samples, study compounds, records, work in progress, other archived materials while in Envigo's possession, or goods and materials in transit;

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errors and omissions from a test that may undermine the usefulness of a study or data from the study;



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although Envigo does not conduct clinical trials, errors or omissions that result in harm to study volunteers during a trial or after regulatory approval of the product to consumers of the product; and



•

risks that Envigo's research models may be contaminated or infected, which could harm the models or humans coming into contact with them despite Envigo's best efforts to implement appropriate protections.

        Envigo tries to limit these risks. In its RMS business, Envigo implements testing, quarantine and veterinary measures to control animal disease. Nevertheless, Envigo has in the past suffered disease in its population, and may suffer outbreaks in the future. In Envigo's CRS and RMS businesses while it endeavors to include in its contracts provisions entitling Envigo to be indemnified or entitling Envigo to a limitation of liability, these provisions do not uniformly protect Envigo against liability arising from certain of Envigo's own actions, such as negligence or misconduct. Moreover, in certain circumstances Envigo may agree to use contracts drafted by its clients, which may not contain clauses that indemnify Envigo or limit Envigo's liability. Envigo could be materially adversely affected if it were required to pay damages or bear the costs of defending any claim which is not covered by a contractual indemnification provision or in the event that a party who must indemnify Envigo does not fulfill its indemnification obligations or which is beyond the level of Envigo's insurance coverage or for which insurance coverage is not available. There can be no assurance that Envigo will be able to maintain such insurance coverage on terms acceptable to it.

Envigo's animal populations may suffer diseases that can damage Envigo's inventory, harm its reputation or result in other liability to it.

        It is important that Envigo's research products be free of diseases, including infectious diseases. Envigo houses in its CRS business a number of different species at close proximity, with new batches being acquired frequently. In its RMS business, the models in its animal production facilities must similarly remain free of contamination. The presence of diseases or infectious agents has the potential to cause substantial loss of animals in Envigo's inventory, to result in harm to humans or the public if the disease cannot be contained to animals in inventory and/or to negatively impact the quality of the research results. These risks may differ substantially according to species. In rodents most infections are without any apparent clinical signs and therefore pose a risk to the scientific quality of the research performed on the animals rather than to humans. Envigo seeks to minimize the risk of these species being infected by the stringent health monitoring programs in place at the supplier and Envigo itself in Envigo's RMS facilities. The same applies to a certain degree to primates, where all animals are serologically tested for specific diseases. The main concern in this species is the potential of any zoonotic infectious disease to cause harm to humans. Again, the risk is substantially minimized by efficient quarantine and health monitoring programs at supplies and after acquisition. Nevertheless, Envigo has in the past suffered disease in its animal populations, and may suffer outbreaks in the future. Diseases in cats and dogs bear less risk to Envigo as efficient vaccination programs are available and followed in these species. Farm animals may be carriers of diseases, which may cause significant losses in animal numbers and are of particular public interest, including foot and mouth disease. Any significant disease outbreak at Envigo has the potential to harm Envigo's reputation or have a material adverse effect on its financial condition, results of operations, and cash flows. There is also the risk that disease from research models Envigo produces may affect customer facilities.

        If disease or contamination occurs in Envigo's animal population, it typically requires remediation and cleanup efforts that could be costly and time consuming. In certain circumstances, it can require the temporary or permanent closure of an affected facility. Envigo has experienced such closures in the

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past. The possibility for genetic mix ups or mutations also exists and may adversely affect Envigo's relationship with customers affected by such mix ups or mutations and may result in an affected customer requesting compensation for damages. Such mix ups or mutations may also affect Envigo's customers' animal colonies.

Envigo is subject to environmental, health and safety requirements and risks as a result of which it may incur significant costs, liabilities and obligations.

        Envigo is subject to a variety of federal, state, local and foreign environmental laws, regulations, initiatives and permits that govern, among other things: the emission and discharge of materials, including greenhouse gases, in air, land and water; the remediation of soil, surface water and groundwater contamination; the generation, storage, handling, use, disposal and transportation of regulated materials and wastes, including biomedical and radioactive wastes; and health and safety. Failure to comply with these laws, regulations or permits could result in fines or sanctions, obligations to investigate or remediate existing or potential contamination, third-party property damage claims, personal injury claims, natural resource damages claims, or modification or revocation of operating permits and may lead to temporary or permanent business interruptions. Pursuant to certain environmental laws, Envigo may be held strictly, and under certain circumstances jointly and severally liable for costs of investigation and remediation of contaminated sites which Envigo currently owns or operates, or sites Envigo or its predecessors have owned or operated in the past. Further, Envigo could be held liable at sites where it has sent waste for disposal.

        Environmental laws, regulations and permits, and the enforcement thereof, change frequently and have tended to become more stringent over time. Compliance with the requirements of laws and regulations may increase capital costs and operating expenses, or necessitate changes to Envigo's production processes.

        Envigo endeavors to conduct its operations according to all legal requirements, but it may not be in complete compliance with such laws and regulations at all times. Envigo uses, and in the past has used, hazardous materials and generates, and in the past has generated, hazardous wastes. Envigo cannot eliminate the risk of accidental contamination or injury from these materials. In the event of such an accident, Envigo could be held liable for any resulting damages and incur liabilities which exceed Envigo's resources. Envigo's costs, liabilities and obligations relating to environmental matters may have a material adverse effect on its business, financial condition, prospect, results of operations and cash flows.

Envigo may not be able to successfully develop and market or acquire new services.

        Envigo may seek to develop and market new services that complement or expand its existing business or expand its service offerings through acquisition. If Envigo is unable to develop new services and/or create demand for those newly developed services, or expand its service offerings through acquisition, its future business growth, results of operations, prospects, financial condition, and cash flows could be adversely affected.

Upgrading and integrating newly acquired business systems could result in implementation issues and business disruptions.

        Envigo has embarked upon an integration and upgrade, as appropriate, to many of its legacy business systems including Customer Relationship Management and Enterprise Resource Planning ("ERP") systems and financial, accounting and information technology systems. In general, the process of planning and preparing for these types of integrated, wide-scale implementations is complex, and Envigo is required to address a number of challenges including data conversion, system cutover and user training. Problems in any of these areas could cause operational problems during implementation

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including delayed shipments, missed sales, billing and accounting errors, delayed or reduced collections and other operational issues. There have been numerous instances of companies experiencing difficulties with the implementation of ERP and other systems which resulted in negative business consequences.

A cyber attack against Envigo's computer systems and information could adversely affect Envigo's operating results and financial condition.

        As a routine element of Envigo's business, it collects, analyzes and retains substantial amounts of data pertaining to the non-clinical studies Envigo conducts for its customers, much of which is highly sensitive and confidential. As a result, Envigo operates large and complex computer systems that contain significant amounts of confidential client data. Envigo's information technology systems also contain proprietary and other confidential information related to its business, such as business plans and employee information.

        Envigo has taken measures to protect the data on its computer systems from unauthorized access or intrusion, including through its information technology systems, and where Envigo considers it to be appropriate, through the implementation of security measures at its research facilities and by entering into confidentiality agreements with employees and consultants. However, any systems and processes that are designed to protect confidential information and prevent data loss and other security attacks cannot provide absolute security. Failure to prevent or mitigate data loss or future security incidents could expose Envigo or its customers to a risk of loss or misuse of such information, cause customers to lose confidence in its data protection measures, damage its reputation, adversely affect its operating results or result in litigation or potential liability. In addition, given the extensive reliance of Envigo's business on information technology and the potentially substantial investment that would be required for new technology infrastructure, any substantial disruption or resulting loss of data that is not avoided or corrected by backup measures could adversely affect Envigo's business and operations.

        In January 2018, Envigo experienced criminal cyber-attacks that involved unauthorized access to its corporate network that led to disruptions of Envigo's operations. Envigo is in the process of restoring its operations and remedying the effects of the cyber-attacks, but the business disruption and related business consequences may have a material adverse impact on Envigo's business, customer relations and financial performance.

        Envigo maintains insurance coverage that may, subject to policy terms and conditions, cover certain aspects of cyber risks. Nevertheless, this insurance coverage is subject to a retention amount and, depending on the incident, the insurance coverage may not be sufficient to cover all of Envigo's losses beyond any retention.

If Envigo is unable to identify and successfully complete acquisitions, its business could be adversely affected.

        Envigo may seek to expand its business through acquisitions. However, business and technologies may not be available on terms and conditions Envigo finds acceptable. The terms of Envigo's financing arrangements may impose restrictions on Envigo's ability to make acquisitions. Envigo may devote time and resources investigating and negotiating with potential acquisition targets, but not consummate the transactions. Even if consummated, factors which may affect Envigo's ability to grow successfully through acquisitions include:

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difficulties and expenses in connection with integrating the acquired companies and achieving the expected benefits;



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diversion of management's attention from current operations;



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the possibility that Envigo may be adversely affected by risk factors facing the acquired companies;

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potential losses resulting from undiscovered liabilities of acquired companies not covered by the indemnification Envigo may obtain from the seller;



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difficulties in retaining customers of the acquired business;



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risks of not being able to overcome differences in foreign business practices, language and other cultural barriers in connection with the acquisition of foreign companies; and



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loss of key employees of the acquired companies.

        In the event that an acquired business or technology does not meet Envigo's expectations, Envigo's results of operations may be adversely affected.

Envigo's non-US locations account for a significant percentage of its revenues, exposing Envigo to risks associated with operating internationally.

        In 2016, more than 60% of Envigo's net revenues from continuing operations were generated by its facilities outside the United States. As a result of these foreign sales and facilities, Envigo's operations are subject to a variety of risks unique to international operations, including the following:

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exposure to local economic conditions;



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currency exchange rate fluctuations;



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changes in tax law;



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potential restrictions on the transfer of funds;



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unexpected changes in regulatory requirements;



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exposure to liabilities under the US Foreign Corrupt Practices Act or the UK Antibribery Act;



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government imposed investment and other restrictions or requirements;



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exposure to local social unrest, including any resultant acts of war, terrorism or similar events;



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exposure to local public health issues and the resultant impact on economic and political conditions;



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difficulty enforcing agreements and collecting receivables through certain legal systems;



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more expansive legal rights of employees, including specifically those applicable to Envigo's European operations;



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variations in protection of intellectual property and other legal rights; and



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export and import and trade restrictions (such as antidumping duties, tariffs or embargoes).

Envigo is exposed to exchange rate fluctuations.

        Envigo operates on a worldwide basis and generally invoices its customers in the currency of the country in which the customer operates. Envigo does not hedge against this exposure. While exposure to exchange rate fluctuations may be limited since Envigo's sales are generally denominated in the same currency as its costs, trading exposures to currency fluctuations may nonetheless occur as a result of certain sales contracts, performed for customers in a different country than the testing site, which are denominated in a currency different from the site's currency. There can be no assurance Envigo will not suffer adverse impacts from currency fluctuations in the future. Moreover, since Envigo operates on an international basis, movements in exchange rates, particularly of British pounds, can have a significant impact on Envigo's price competitiveness vis a vis competitors who operate in currencies other than British pounds or US dollars. Exchange rate fluctuations against the British

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pound have shown increased volatility since Brexit. Envigo's indebtedness is denominated almost entirely in US dollars whereas Envigo earns significant revenues (approximately 64% of total net revenues from continuing operations in 2016) in other currencies. This may adversely impact Envigo's ability to meet its debt obligations.

Envigo is exposed to changes in interest rates.

        Envigo is exposed to changes in interest rates while conducting normal business operations as a result of ongoing financing activities. The majority of Envigo's debt is comprised of floating interest rate borrowings linked to London Interbank Offered Rate ("LIBOR"). As of September 30, 2017, a 100-basis point increase in LIBOR would increase Envigo's annual pre-tax interest expense by approximately $4.4 million.

Envigo's backlog may not be indicative of future results.

        Envigo's backlog of approximately $146 million as of December 31, 2016 is based on anticipated CRS revenue from uncompleted projects that Envigo customers have awarded and Envigo believes to be firm commitments. Once work begins on a project, net revenue is recognized over the duration of the project. Backlog is the amount of revenue that remains to be earned and recognized on signed contracts. Contracts included in backlog are generally subject to termination by Envigo's customers at any time. In the event that a customer cancels a contract, Envigo typically would be entitled to receive payment for all services performed up to the cancellation date and subsequent customer-authorized services related to terminating the cancelled project. However, it may be difficult to collect such post-termination payments from certain customers. The duration of the projects included in Envigo's backlog range from a few days to several years.

        Envigo's backlog may not be indicative of its future results and Envigo cannot assure you that it will realize all the anticipated future revenue reflected in its backlog. A number of factors may affect backlog, including:

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the variable size and duration of the projects;



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the delay of projects;



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the change in the scope of work during the course of a project; and



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the cancellation of such contracts by Envigo's customers.

        Also, if projects are delayed, they will remain in backlog but will not generate revenue at the time originally expected. Cancellation or delay of a large contract or multiple smaller contracts could result in under-utilized resources and could require an adjustment to Envigo's backlog, negatively affecting Envigo's net revenue and results of operations. The historical relationship of backlog to revenues actually realized by Envigo should not be considered indicative of future results.

Envigo's contracts are generally terminable on little or no notice. Termination of a large contract for services or multiple contracts for services or product purchases could adversely affect Envigo's revenue and profitability.

        In general, Envigo's customers may terminate the agreements that they enter into with Envigo or reduce the scope of services under these contracts upon little or no notice. Contracts may be terminated for various reasons, including:

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unexpected or undesired study results;



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the loss of funding for the particular research study;



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the failure of products to satisfy technical or safety requirements;

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production problems resulting in shortages of the product being tested;



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adverse reactions to the product being tested;



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regulatory restrictions placed on the product being tested; or



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the customer's decision to forego or terminate a particular study or compound.

        The loss, reduction in scope or delay of a large contract or the loss or delay of multiple smaller contracts could materially adversely affect Envigo's business.

Because most of Envigo's CRS revenues are from fixed price contracts, these contracts may be subject to under-pricing and cost overruns.

        The majority of Envigo's CRS contracts with its customers are fixed price contracts with set limits on amounts Envigo can charge for its services, creating the risk of cost overruns under these contracts. Envigo typically has some flexibility under these contracts to adjust the price to be charged if it is asked to provide additional services. If Envigo did have to bear significant costs of under-pricing or cost overruns under these contracts, its business, financial condition and operating results could be adversely affected.

Envigo depends heavily on its senior management team, and the loss of any member may adversely affect it.

        Envigo believes its success depends on the continued availability of its senior management team, including Adrian Hardy (CEO) and Patricia Henahan (CFO). If one or more members of the senior management team were unable or unwilling to continue in their present positions, those persons would likely be difficult to replace and Envigo's business would likely be harmed. If any of Envigo's key employees were to join a competitor or to form a competing company, some of Envigo's customers might choose to use the services of that competitor or new company instead of Envigo. Furthermore, customers or other companies seeking to develop in-house capabilities may hire away some of Envigo's senior management or key employees. The loss of one or more of these key employees could adversely affect Envigo's business.

Envigo must recruit and retain qualified personnel.

        Because of the specialized scientific nature of Envigo's business, it is highly dependent upon qualified scientific, technical and managerial personnel. There is intense competition for qualified personnel in the biopharmaceutical field. The shortage of qualified scientific, technical and managerial personnel, or other factors, might lead to increased recruiting, relocation and compensation costs for these professionals. These increased costs might reduce Envigo's profit margins or make hiring new personnel impracticable. In the future it may not be able to attract and retain the qualified personnel necessary for the conduct and further development of its business. The loss of the services of existing personnel, as well as the failure to recruit additional key scientific, technical and managerial personnel in a timely manner, could have a material adverse effect on Envigo's ability to expand its businesses and remain competitive in the segments in which it participates.

Actions of animal rights activists may affect Envigo's business.

        Envigo's CRS business utilizes animals (predominantly rodents) to test the safety and efficacy of drugs. Envigo's RMS business provides animal research models (predominantly rodents) to its customers. Such activities are required for the registration of products under regulatory regimes in the United States, Europe, Japan and other countries. CROs, including Envigo, biopharmaceutical companies and other research organizations have been targeted by animal rights activists who oppose all testing on animals, for whatever purpose, including the animal testing activities in support of safety and efficacy testing for drug development. These groups, which include groups directed at the industry

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and Envigo, have publicly stated that their goal is to stop animal testing. Acts of vandalism and other acts by animal rights activists who object to the use of animals in product development could have a material adverse effect on Envigo's business. These groups have targeted not only CROs and biopharmaceutical companies, but also third parties including customers, suppliers, advisors, financial advisors, lenders and investors.

Unfavorable global economic conditions could negatively impact Envigo's operating results and financial condition.

        Unfavorable global economic conditions could negatively affect Envigo's business. While it is difficult for Envigo to predict the impact of general economic conditions on its business, these conditions could reduce customer demand for some of its services, which could cause its revenue to decline. Also, Envigo's customers, particularly smaller biotechnology companies which are especially reliant on the credit and capital markets, may not be able to obtain adequate access to credit or equity funding, which could affect their ability to retain Envigo's services or make timely payments to Envigo. If that were to occur, Envigo could be required to increase its allowance for doubtful accounts, and the number of days of sales outstanding for its accounts receivable could increase. For these reasons, among others, if the global economic conditions stagnate or decline, Envigo's operating results and financial condition could be adversely affected.

Envigo relies on its facilities and any disruption in their operation could materially adversely impact Envigo.

        Envigo relies on of its facilities. In particular, Envigo's CRS laboratories and RMS isolator and barrier breeding facilities are highly specialized and would be difficult to replace in a short period of time. Any event that causes a disruption of the operation of these facilities might impact Envigo's ability to provide services and products to its customers and therefore could have a material adverse effect on its financial condition, results of operations and cash flows.

If Envigo experiences a breach of the confidentiality of the information it holds or of the security of its computer systems, it could adversely affect Envigo's operating results and financial condition.

        As a routine element of Envigo's business, it collects, analyzes and retains substantial amounts of data pertaining to the non-clinical studies Envigo conducts for its customers, much of which is highly sensitive and confidential. As a result, Envigo operates large and complex computer systems that contain significant amounts of confidential client data. Envigo's contracts with its customers typically contain provisions that require Envigo to keep confidential the information received from its customers and generated from these studies. Unauthorized persons could attempt to gain entry to this confidential information for the purpose of stealing or otherwise accessing confidential data or other information. Envigo believes that it has taken adequate measures to protect its data and its customers' confidential information from unauthorized access or intrusion, including, where Envigo considers it to be appropriate, through the implementation of security measures at its research facilities and by entering into confidentiality agreements with employees and consultants. While Envigo continues to monitor, and to improve and enhance where appropriate, its systems in this regard, in the event that Envigo's efforts are unsuccessful and the confidentiality of any information is compromised, Envigo could suffer significant harm. In addition, as with all information technology, Envigo's systems could become vulnerable to potential damage or interruptions from fires, blackouts, telecommunications failures and other unexpected events, as well as to break-ins, sabotage or intentional acts of vandalism. Given the extensive reliance of Envigo's business on information technology and the substantial investment that would be required for new technology infrastructure, any substantial disruption or resulting loss of data that is not avoided or corrected by backup measures could adversely affect Envigo's business and operations.

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Potential changes in tax law in Europe and the United Kingdom could adversely affect Envigo's operating results and financial condition.

        Envigo has substantial operations in the UK, which currently benefit from favorable corporate tax arrangements. Envigo receives benefits from enhanced deductions and accelerated tax depreciation allowances in the UK. Any reduction in the availability or amount of these deductions would be likely to have a material adverse effect on profits, cash flow and Envigo's effective tax rate.

        On July 18, 2013, a change was enacted in UK Tax Legislation in relation to research and development expenditures, giving companies the option of recognizing research and development credits as a reduction of cost of sales. Envigo adopted the new approach effective April 1, 2013. Envigo has significant tax losses that can be offset against future trading profits and help to minimize cash tax payments. There are limitations in the amount of losses that can be utilized each year. Envigo continues to maintain a full valuation allowance against the deferred tax assets in the UK until sufficient positive evidence exists to reduce or eliminate the allowance.

Some of Envigo's customers depend on government funding of research and development and a reduction in that funding may adversely affect Envigo's business.

        A portion of sales in Envigo's RMS business is derived from customers at academic institutions and research laboratories whose funding is partially dependent on funding from government sources, including the US National Institutes of Health ("NIH") and UK/EU equivalents. Such funding can be difficult to forecast as it may be subject to the political process. Envigo's sales may be adversely affected if its customers delay purchases as a result of uncertainties surrounding the approval of government budget proposals. A reduction in government funding for the NIH or other government research agencies could adversely affect Envigo's business and its financial results. There can be no certainty that government research funding will be directed towards projects and studies that require use of Envigo's services and products.

Impairment of goodwill or other intangible assets may adversely impact future results of operations.

        Envigo has intangible assets, including goodwill and other indefinite-lived intangible assets on its balance sheet due to acquisitions of businesses. The initial identification and valuation of these intangible assets and the determination of the estimated useful lives at the time of acquisition involve use of management judgement and estimates. The estimates are based on input from accredited valuation consultants and reviews of projected future income cash flows. The use of alternative estimates and assumptions might have increased or decreased the estimated fair value of Envigo's intangible assets. If the future growth and operating results of the business are not as strong as anticipated this could impact the assumptions in calculating the fair value of intangible assets. To the extent that intangible assets are impaired, their carrying value will be written down to their implied fair value and a charge made to the income from continuing operations that could materially affect Envigo's operating results. As of September 30, 2017 and December 31, 2016, the carrying amount of goodwill and other intangible assets was approximately $232.4 million and $235.3 million, respectively, on Envigo's consolidated balance sheet.

Envigo's substantial levels of outstanding indebtedness could adversely affect its financial condition, limit its ability to react to changes in the economy or its industry and prevent Envigo from meeting its obligations under the Envigo Credit Agreements and/or the Existing Third Lien Indenture.

        As of September 30, 2017 and December 31, 2016, Envigo had approximately $458.0 million and $443.6 million, respectively, of indebtedness, net of unamortized financing costs, warrants and discounts.

        Effective March 15, 2012, Envigo completed an offering of approximately $22.4 million principal amount of 15.00% Third Lien Debt due 2020 issued by Envigo Laboratories, Inc. (the "Third Lien Debt") which has since grown to approximately $46.3 million due to payment in kind interest.

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        Effective April 29, 2014, in connection with the acquisition of Harlan Laboratories Holdings Corp. ("Harlan"), Envigo incurred additional indebtedness of $310.4 million, comprised of (a) $150.0 million of First Lien Notes pursuant to that certain First Lien Credit Agreement, dated as of April 29, 2014 (the "First Lien Credit Agreement") among Envigo Laboratories, the several guarantors from time to time party thereto, the lenders from time to time party thereto and Wilmington Trust, National Association ("Wilmington") as Administrative Agent and Collateral Agent to the First Lien Credit Agreement, (b) $130.475 million of Second Lien Notes pursuant to that certain Second Lien Credit Agreement, dated as of April 29, 2014 (the "Second Lien Credit Agreement") among Envigo Laboratories, the several guarantors from time to time party thereto, the lenders from time to time party thereto and Wilmington as Administrative Agent and Collateral Agent to the Second Lien Credit Agreement, and (c) $30.0 million of Second Lien Liquidity Notes pursuant to that certain Second Lien Liquidity Facility Credit Agreement, dated as of April 29, 2014 (the "Second Lien Liquidity Facility Credit Agreement"), among Envigo Laboratories, the several guarantors from time to time party thereto, the lenders from time to time party thereto and Wilmington as Administrative Agent and Collateral Agent to the Second Lien Liquidity Facility Credit Agreement.

        Effective November 3, 2016, Envigo incurred additional indebtedness of approximately $130 million pursuant to that certain First Lien Credit Agreement dated as of November 3, 2016 among Envigo Holdings, Inc., Envigo Laboratories, Inc., the several guarantors party thereto from time to time and Jefferies Finance LLC as Administrative Agent (the "New First Lien Credit Agreement" and together with the First Lien Credit Agreement, Second Lien Credit Agreement and Second Lien Liquidity Facility Credit Agreement, the "Envigo Credit Agreements"). As of September 30, 2017, Envigo's net indebtedness, of approximately $458.0 million consisted of $46.3 million of indebtedness related to the Third Lien Debt, $268.0 million of indebtedness of the First and Second Lien Notes, $25.6 million of indebtedness of the Second Lien Liquidity Notes and $128.3 million relating to the New First Lien Credit Agreement. This debt represents approximately 76% of Envigo's total capitalization. Envigo's substantial level of indebtedness increases the risk that it may be unable to generate cash sufficient to pay amounts due in respect of its indebtedness. Envigo's substantial indebtedness could have other important consequences to you and significant effects on Envigo's business, including:

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increasing Envigo's vulnerability to adverse changes in general economic, industry and competitive conditions;



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requiring a substantial portion of cash flow from operations to be dedicated to the payment of principal and interest on Envigo's indebtedness, thereby reducing its ability to use its cash flow to fund its operations, capital expenditures and future business opportunities;



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making it more difficult for Envigo to satisfy its obligations with respect to its indebtedness, and any failure to comply with the obligations of any of its debt instruments, including financial or restrictive covenants and borrowing conditions, could result in an event of default under the Existing Third Lien Indenture governing the Third Lien Debt or the agreements governing other indebtedness and result in the acceleration of Envigo's outstanding debt;



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require Envigo to repatriate cash for debt service from its foreign subsidiaries resulting in dividend tax costs or require it to adopt other disadvantageous tax structures to accommodate debt service payments;



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restricting Envigo from making strategic acquisitions or causing it to make non-strategic divestitures;

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limiting Envigo's ability to obtain additional financing for working capital, capital expenditures, product development, debt service requirements, acquisitions and general corporate or other purposes, including to repurchase the notes from the holders upon a change of control; and



•

limiting Envigo's flexibility in planning for, or reacting to, changes in its business or market conditions and placing it at a competitive disadvantage compared to its competitors who have less debt and who, therefore, may be able to take advantage of opportunities that Envigo's leverage prevents it from pursuing.

        Envigo's liquidity needs could vary significantly and may be affected by general economic conditions, industry trends, performance and many other factors not within Envigo's control. If it is unable to generate sufficient cash flow from operations in the future to service its debt, Envigo may be required to refinance all or a portion of its existing debt. However, Envigo may not be able to refinance its debt or obtain any new or additional debt on favorable terms or at all.

Envigo may incur additional amounts of debt, including secured indebtedness, which could further exacerbate the risks associated with its current level of indebtedness and allow holders of the future secured debt to exercise certain rights and remedies with respect to the collateral securing the notes.

        Envigo may incur additional indebtedness in the future, including secured indebtedness. Although the Existing Third Lien Indenture and the Envigo Credit Agreements governing its debt contain restrictions on the incurrence of additional indebtedness, these restrictions are subject to a number of qualifications and exceptions, and under certain circumstances, the amount of indebtedness that could be incurred in compliance with these restrictions could be substantial. If new debt is added to Envigo's existing debt levels, the related risks that it now faces would increase.

Envigo's debt agreements contain or future debt agreements may contain restrictions that will limit its flexibility in operating its business.

        The Existing Third Lien Indenture and the Envigo Credit Agreements contain, and future debt agreements may contain, various covenants that limit Envigo's ability to engage in specified types of transactions. These covenants limit Envigo's ability to, among other things:

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incur or guarantee additional indebtedness and issue preferred stock;



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pay dividends and make other restricted payments;



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enter into agreements restricting the payment of dividends or other distributions from Envigo's restricted subsidiaries;



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create or incur liens;



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make investments;



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transfer or sell assets;



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engage in transactions with affiliates; and



•

merge or consolidate with other companies or transfer all or substantially all of Envigo's or their assets.

Envigo's pension plans are underfunded and may require increased contribution payments.

        Envigo provides defined benefit plans for certain of its past or current UK employees. While these plans have been closed to future participants, the plans are as of December 31, 2016 underfunded by approximately $57.1 million to meet prospective obligations to plan participants. Obligations under these plans reflect certain actuarial and other assumptions. The funding requirements and cost of these plans are dependent upon these assumptions and various other factors, including the actual return on

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plan assets, discount rates, participant demographics and changes in pension regulations. Envigo's future costs and funding obligations can increase or decrease significantly depending upon these factors.

Brexit may adversely affect Envigo's business.

        On June 23, 2016, the UK held a referendum in which voters approved an exit from the European Union, commonly referred to as Brexit. Brexit has caused significant disruption and uncertainty in the UK and worldwide business communities and has resulted in volatile currency exchange fluctuations. Approximately 46.5% of Envigo's revenue, and an even greater proportion of Envigo's earnings, are generated in the UK in pounds sterling. The procedures and timings for Brexit are uncertain. Brexit could potentially lead to divergent laws throughout the EU, including in countries where Envigo does business, which could lead to uncertain business relations and revenue generation in those countries.

Envigo may not be able to timely and effectively implement controls and procedures required by Section 404 of the Sarbanes Oxley Act of 2002 that will be applicable to us after the business combination.

        Envigo is currently not subject to Section 404 of the Sarbanes Oxley Act of 2002. However, following the business combination, the combined company may be required to provide management's attestation on internal controls commencing with the Company's annual report for fiscal 2018. The standards required for a public company under Section 404 of the Sarbanes-Oxley Act of 2002 are significantly more stringent than those required of Envigo as a privately-held company. Management may not be able to effectively and timely implement controls and procedures that adequately respond to the regulatory compliance and reporting requirements that will be applicable to Envigo after the business combination. If we are not able to implement the additional requirements of Section 404 in a timely manner or with adequate compliance, we may not be able to assess whether our internal controls over financial reporting are effective, which may subject us to adverse regulatory consequences and could harm investor confidence and the market price of ENVG common stock.

New U.S. tax legislation could adversely affect Envigo's business.

        On December 22, 2017, the current U.S. administration signed an act referred to as the "Tax Cuts and Jobs Act" (the "TCJA"), generally effective for taxable years beginning after December 31, 2017. The TCJA is complex and includes significant amendments to the Internal Revenue Code of 1986 (as amended, the "Code"), including amendments that significantly change the taxation of offshore earnings and the deductibility of interest. Envigo is currently assessing the impact of the TCJA on its business and consolidated financial statements. In connection with that ongoing assessment, Envigo has identified at least three provisions that may have a material and adverse effect on Envigo's business. First, the TCJA generally will require Envigo to include in income with respect to its 2017 taxable year any undistributed and previously untaxed earnings of its foreign subsidiaries, subject to adjustments. Second, going forward, the TCJA generally will subject Envigo to a current tax on any undistributed earnings of its foreign subsidiaries to the extent such earnings are considered to be "global intangible low-taxed income ("GILTI"), subject to certain deductions and adjustments. Third, the TCJA generally will disallow Envigo's U.S. interest deductions going forward to the extent such deductions exceed 30% of its U.S. "adjusted taxable income" (which will be roughly equivalent to EBITDA through 2022 and to EBIT thereafter). These, and other provisions of the TCJA, may have a material and adverse impact on Envigo's business and financial condition and the value of ENVG's common shares. Envigo is continuing to assess the impact of the TCJA. Holders should consult their tax advisors about the TCJA and its potential impact on Envigo's business and their ownership of ENVG common shares.

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Risks Related to AHPAC and the Business Combination

The initial shareholders and management team have agreed to vote in favor of the business combination, regardless of how public shareholders vote.

        As of the date hereof, the initial shareholders own 100% of AHPAC's outstanding Class B shares and approximately 20% of AHPAC's outstanding ordinary shares in total. AHPAC's amended and restated memorandum and articles of association provide that the business combination will be approved if AHPAC receives the affirmative vote of a majority of the ordinary shares voted at the general meeting, including the Class B ordinary shares. Accordingly, the agreement by the initial shareholders to vote in favor of the business combination will increase the likelihood that AHPAC will receive the requisite shareholder approval for the business combination.

The sponsor, certain members of the AHPAC Board and AHPAC's officers have interests in the business combination that are different from or are in addition to other shareholders in recommending that shareholders vote in favor of approval of the Business Combination Proposal and approval of the other proposals described in this proxy statement/prospectus.

        When considering the AHPAC Board's recommendation that AHPAC's shareholders vote in favor of the approval of the Business Combination Proposal, AHPAC's shareholders should be aware that the directors and officers of AHPAC have interests in the business combination that may be different from, or in addition to, the interests of AHPAC's shareholders. See the section titled " The Business Combination—Interests of Certain Persons in the Business Combination " for further information.

The initial shareholders, including the sponsor and AHPAC's independent directors, hold a significant number of AHPAC Common Shares. They will lose their entire investment in AHPAC if a business combination is not completed.

        The initial shareholders currently own 7,750,000 AHPAC Class B ordinary shares. The AHPAC Class B ordinary shares will be worthless if AHPAC does not complete an initial business combination. In addition, the initial shareholders own, in the aggregate, 16,400,000 private placement warrants exercisable for an aggregate of 8,200,000 AHPAC Class A ordinary shares at an exercise price of $11.50 per share, which will also be worthless if AHPAC does not complete a business combination by October 14, 2018. The personal and financial interests of the sponsor, AHPAC's executive officers and directors may influence their motivation in completing the business combination and influencing the operation of ENVG after the business combination has been consummated.

The sponsor, officers and directors will not be eligible to be reimbursed for their out-of-pocket expenses if a business combination is not completed.

        At the closing of the business combination, the sponsor, executive officers and directors, or any of their respective affiliates, will be reimbursed for any out-of-pocket expenses incurred in connection with activities on AHPAC's behalf, such as identifying potential target businesses and performing due diligence on suitable business combinations. There is no cap or ceiling on the reimbursement of out-of-pocket expenses incurred in connection with activities on AHPAC's behalf. The personal and financial interests of the sponsor, executive officers and directors may influence their motivation in identifying and selecting a target business combination and completing the business combination.

The sponsor, directors or officers or their affiliates may elect to purchase shares from public shareholders, which may influence a vote on a proposed business combination and reduce the public "float" of ENVG Class A common stock.

        The sponsor, ENVG's directors or executive officers or their affiliates may purchase shares in privately negotiated transactions or in the open market either prior to or following the completion of the business combination, although they are under no obligation to do so. Such a purchase may include

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a contractual acknowledgement that such shareholder, although still the record holder of shares of ENVG common stock, is no longer the beneficial owner thereof and therefore agrees not to exercise its redemption rights. In the event that the sponsor, directors, officers or their affiliates purchase shares in privately negotiated transactions from public shareholders who have already elected to exercise their redemption rights, such selling shareholders would be required to revoke their prior elections to redeem their shares. The purpose of such purchases could be to vote such shares in favor of the business combination and thereby increase the likelihood of obtaining shareholder approval of the business combination or to satisfy closing conditions in the Transaction Agreement regarding required amounts in the trust account and the proceeds from the private placement equaling or exceeding certain thresholds where it appears that such requirements would otherwise not be met. This may result in the completion of the business combination that may not otherwise have been possible.

        In addition, if such purchases are made, the public "float" of ENVG Class A common stock and the number of beneficial holders of ENVG's securities may be reduced, possibly making it difficult to maintain or obtain the quotation, listing or trading of AHPAC's securities on NASDAQ or another national securities exchange or reducing the liquidity of the trading market for ENVG Class A common stock.

Public shareholders may experience dilution as a consequence of, among other transactions, the issuance of ENVG Class A common stock as consideration in the business combination, the equity financing (if any) and the Debt Refinancing (if any). Having a minority share position may reduce the influence that AHPAC's current shareholders have on the management of AHPAC.

        It is anticipated that, upon completion of the business combination: (i) AHPAC's public shareholders will retain an ownership interest of approximately 57.7% in ENVG; (ii) the sponsor will own approximately 5.6% of ENVG and (iii) the Selling Equityholders will own approximately 36.7% of ENVG. The ownership percentages of ENVG following the business combination assume that no shares are elected to be redeemed and do not take into account (a) the warrants to purchase ENVG Class A common stock that will be issued in connection with and remain outstanding following the business combination, or (b) the issuance of any ENVG Class A common stock in connection with the equity financing (if any). For more information, please see the sections entitled " Summary of the Proxy Statement/Prospectus—Ownership of AHPAC " and " Unaudited Pro Forma Condensed Combined Financial Information ." See the section titled " The Business Combination—The Transaction Agreement—Equity Financing " beginning on page 86 of this proxy statement/prospectus for further details regarding AHPAC's obligations in connection with the equity financing. See the section titled " The Transaction Agreement—Related Agreements—Financing Arrangements " beginning on page 129 of this proxy statement/prospectus for further details regarding Envigo's obligations in connection with a Debt Refinancing.

        To the extent that any warrants to purchase ENVG Class A common stock that will be issued in connection with and remain outstanding following the business combination are exercised, current shareholders may experience substantial dilution. Such dilution could, among other things, limit the ability of AHPAC's current shareholders to influence management of AHPAC through the election of directors following the business combination.

There can be no assurance that ENVG Class A common stock that will be issued in connection with the business combination will be approved for listing on NASDAQ following the consummation of the business combination, or that AHPAC will be able to comply with the continued listing standards of NASDAQ.

        The AHPAC Class A ordinary shares and public warrants are currently listed on NASDAQ. AHPAC's continued eligibility for listing may depend on, among other things, the number of public shares that are redeemed. If, after the business combination, NASDAQ delists ENVG Class A common

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stock from trading on its exchange for failure to meet the listing standards, ENVG's stockholders could face significant material adverse consequences including:

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a limited availability of market quotations for ENVG's securities;



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reduced liquidity for ENVG's securities;



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a determination that ENVG Class A common stock are a "penny stock" which will require brokers trading in ENVG Class A common stock to adhere to more stringent rules and possibly result in a reduced level of trading activity in the secondary trading market for ENVG's securities;



•

a limited amount of news and analyst coverage; and



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a decreased ability to issue additional securities or obtain additional financing in the future.

        The National Securities Markets Improvement Act of 1996, which is a federal statute, prevents or preempts the states from regulating the sale of certain securities, which are referred to as "covered securities." Because AHPAC Class A ordinary shares and public warrants are listed on NASDAQ, they are covered securities. Although the states are preempted from regulating the sale of AHPAC's securities, the federal statute does allow the states to investigate companies if there is a suspicion of fraud, and, if there is a finding of fraudulent activity, then the states can regulate or bar the sale of covered securities in a particular case. While AHPAC is not aware of a state, other than the state of Idaho, having used these powers to prohibit or restrict the sale of securities issued by blank check companies, certain state securities regulators view blank check companies unfavorably and might use these powers, or threaten to use these powers, to hinder the sale of securities of blank check companies in their states. Further, if the shares were no longer listed on NASDAQ, AHPAC's securities would not be covered securities and AHPAC would be subject to regulation in each state in which AHPAC offers securities.

A significant portion of ENVG Class A common stock following the business combination will be restricted from immediate resale, but may be sold into the market in the future. This could cause the market price of ENVG Class A common stock to drop significantly, even if our business is doing well.

        Sales of a substantial number of shares of common stock in the public market could occur at any time. These sales, or the perception in the market that the holders of a large number of shares intend to sell shares, could reduce the market price of ENVG Class A common stock.

        It is anticipated that, upon completion of the business combination: (i) AHPAC's public shareholders will retain an ownership interest of approximately 57.7% in ENVG; (ii) the sponsor will own approximately 5.6% of ENVG and (iii) the Selling Equityholders will own approximately 36.7% of ENVG. The ownership percentages of ENVG following the business combination assume that no shares are elected to be redeemed and do not take into account (a) the warrants to purchase ENVG Class A common stock that will be issued in connection with and remain outstanding following the business combination, or (b) the issuance of any ENVG Class A common stock in connection with the equity financing (if any). For more information, please see the sections entitled " Summary of the Proxy Statement/Prospectus—Ownership of AHPAC " and " Unaudited Pro Forma Condensed Combined Financial Information ."

        At the closing of the business combination, AHPAC, the sponsor and the restricted stockholders will enter into the Amended and Restated Registration Rights Agreement, pursuant to which, among other things. the restricted stockholders will agree not to sell, transfer, pledge or otherwise dispose of shares of common stock or warrants in ENVG it receives in connection with the business combination for either three or six months from the closing of the business combination. As restrictions on resale end, the market price of ENVG Class A common stock could decline if the holders of currently restricted shares sell them or are perceived by the market as intending to sell them.

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AHPAC has no operating history and is subject to a mandatory liquidation and subsequent dissolution requirement. As such, there is a risk that AHPAC will be unable to continue as a going concern if it does not consummate an initial business combination by October 14, 2018. If AHPAC is unable to effect a business combination by October 14, 2018, AHPAC will be forced to liquidate and AHPAC's warrants will expire worthless.

        AHPAC is a blank check company, and as such has no operating history and is subject to a mandatory liquidation and subsequent dissolution requirement. There is a risk that AHPAC will be unable to continue as a going concern if it does not consummate an initial business combination by October 14, 2018. Unless AHPAC amends its memorandum and articles of association to extend the life of AHPAC and certain other agreements into which AHPAC has entered, if it does not complete an initial business combination by October 14, 2018, it will: (i) cease all operations except for the purpose of winding up; (ii) as promptly as reasonably possible but not more than ten business days thereafter, redeem the public shares, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the trust account, including interest (which interest shall be net of taxes payable, and less up to $100,000 of interest to pay dissolution expenses) divided by the number of then issued and outstanding public shares, which redemption will completely extinguish public shareholders' rights as shareholders (including the right to receive further liquidation distributions, if any), subject to applicable law; and (iii) as promptly as reasonably possible following such redemption, subject to the approval of AHPAC's remaining shareholders and the AHPAC Board, dissolve and liquidate, subject in each case to AHPAC's obligations under the Cayman Islands law to provide for claims of creditors and the requirements of other applicable law. In the event of such distribution, it is possible that the per share value of the residual assets remaining available for distribution (including trust account assets) will be less than the initial public offering price per public unit in the IPO. In addition, if AHPAC fails to complete an initial business combination by October 14, 2018, there will be no redemption rights or liquidating distributions with respect to AHPAC's public warrants or the private placement warrants, which will expire worthless, unless AHPAC amends AHPAC's amended and restated memorandum and articles of association to extend the life of AHPAC and certain other agreements into which AHPAC has entered.

AHPAC is not required to obtain and has not obtained an opinion from an independent investment banking or accounting firm, and consequently, you may have no assurance from an independent source that the price AHPAC is paying for Envigo is fair from a financial point of view.

        AHPAC is not required to obtain an opinion from an independent investment banking or accounting firm that the price it is paying to acquire Envigo is fair from a financial point of view. The AHPAC Board did not obtain a third-party valuation or fairness opinion in connection with their determination to approve the business combination. In analyzing the business combination, the AHPAC Board and AHPAC's management conducted due diligence on Envigo and researched the industry in which Envigo operates and concluded that the business combination was in the best interests of AHPAC and its stockholders. Accordingly, investors will be relying solely on the judgment of the AHPAC Board in valuing Envigo's business, and the AHPAC Board may not have properly valued the business. The lack of a third-party valuation or fairness opinion may also lead an increased number of public stockholders to vote against the business combination or demand redemption of their shares, which could potentially impact AHPAC's ability to consummate the business combination.

        For more information about AHPAC's decision-making process, see the section entitled " The Business Combination—The AHPAC Board's Reasons for the Approval of the Business Combination ."

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AHPAC and Envigo have incurred and expect to incur significant costs associated with the business combination. Whether or not the business combination is completed, the incurrence of these costs will reduce the amount of cash available to be used for other corporate purposes by AHPAC if the business combination is not completed.

        AHPAC and Envigo expect to incur significant costs associated with the business combination. Even if the business combination is not completed, AHPAC expects to incur approximately $4 million in expenses. These expenses will reduce the amount of cash available to be used for other corporate purposes by AHPAC if the business combination is not completed.

Even if the domestication qualifies as a reorganization under Section 368(a) of the Code, a U.S. Holder generally may still recognize gain with respect to AHPAC Class A ordinary shares at the effective time of the domestication.

        U.S. holders (as defined in " Material U.S. Federal Income Tax Considerations " below) of AHPAC ordinary shares may be subject to U.S. federal income tax as a result of the domestication.

        A U.S. holder who on the day of the domestication beneficially owns (actually or constructively) AHPAC ordinary shares with a fair market value of $50,000 or more, but less than 10% of the total combined voting power of all classes of AHPAC ordinary shares entitled to vote and less than 10% of the total value of all classes of AHPAC ordinary shares, generally will recognize gain (but not loss) in respect of the domestication as if such holder exchanged its AHPAC ordinary shares for ENVG common stock in a taxable transaction, unless such U.S. holder elects in accordance with applicable Treasury regulations to include in income the "all earnings and profits amount" (as defined in the Treasury regulations) attributable to the AHPAC ordinary shares held directly by such holder.

        Additionally, proposed Treasury Regulations with a retroactive effective date have been promulgated under Section 1291(f) of the Code which generally require that, a U.S. person who disposes of stock of a PFIC (as defined in " Material U.S. Federal Income Tax Considerations " below) must recognize gain equal to the excess of the fair market value of such PFIC stock over its adjusted tax basis, notwithstanding any other provision of the Code.

        If AHPAC is considered a PFIC for U.S. federal income tax purposes, these regulations, if finalized in their current form, would generally require U.S. holders of AHPAC ordinary shares to recognize gain on the exchange of AHPAC ordinary shares for ENVG common stock pursuant to the domestication. The tax on any such gain would be imposed at the rate applicable to ordinary income and an interest charge would apply based on complex rules designed to offset the tax deferral to such holders on the undistributed earnings, if any, of AHPAC. The same rule may also apply to a U.S. holder who exchanges AHPAC warrants for ENVG warrants. It is not possible to determine at this time whether, in what form, and with what effective date, final Treasury regulations under Section 1291(f) of the Code will be adopted.

        Because the domestication will occur prior to the redemption of U.S. Holders that exercise redemption rights, U.S. Holders exercising redemption rights will be subject to the foregoing tax consequences regardless of whether they exercise their redemption rights.

         All holders should consult their tax advisors regarding the tax consequences of the domestication. For a more detailed explanation of the tax consequences, see the discussion below in the section entitled " Material U.S. Federal Income Tax Consequences."

Even if AHPAC consummates the business combination, there is no guarantee that the public warrants will ever be in the money, and they may expire worthless and the terms of AHPAC's warrants may be amended.

        The exercise price for AHPAC's warrants is $11.50 per whole AHPAC Class A ordinary share. There is no guarantee that the public warrants will ever be in the money prior to their expiration, and as such, the warrants may expire worthless.

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AHPAC's ability to successfully effect the business combination and to be successful thereafter will be dependent upon the efforts of AHPAC's key personnel, including the key personnel of Envigo whom AHPAC expects to stay with Envigo following the business combination. The loss of key personnel could negatively impact the operations and profitability of AHPAC post-combination business and its financial condition could suffer as a result.

        AHPAC's ability to successfully effect the business combination is dependent upon the efforts of certain key personnel, including the key personnel of Envigo. Although some of AHPAC's key personnel may remain with Envigo in senior management or advisory positions following the business combination, it is possible that AHPAC will lose some key personnel, the loss of which could negatively impact the operations and profitability of AHPAC's post-combination business. AHPAC anticipates that some or all of the management of Envigo will remain in place.

        Envigo's success depends to a significant degree upon the continued contributions of senior management, certain of whom would be difficult to replace. Departure by certain of Envigo's officers could have a material adverse effect on Envigo's business, financial condition, or operating results. Envigo does not maintain key-man life insurance on any of its officers. The services of such personnel may not continue to be available to Envigo.

AHPAC and Envigo will be subject to business uncertainties and contractual restrictions while the business combination is pending.

        Uncertainty about the effect of the business combination on employees and third parties may have an adverse effect on AHPAC and Envigo. These uncertainties may impair AHPAC or Envigo's ability to retain and motivate key personnel and could cause third parties that deal with any of us or them to defer entering into contracts or making other decisions or seek to change existing business relationships. If key employees depart because of uncertainty about their future roles and the potential complexities of the business combination, AHPAC or Envigo's business could be harmed.

AHPAC may waive one or more of the conditions to the business combination.

        AHPAC may agree to waive, in whole or in part, one or more of the conditions to AHPAC's obligations to complete the business combination, to the extent permitted by AHPAC's amended and restated memorandum and articles of association and applicable laws. For example, it is a condition to AHPAC's obligations to close the business combination Envigo performed and complied in all material respects with the obligations required to be performed or complied with by Envigo under the Transaction Agreement. However, if the AHPAC Board determines that a breach of this obligation is not material, then the Board may elect to waive that condition and close the business combination. AHPAC may not waive the condition that AHPAC's shareholders approve the business combination. Please see the section entitled " The Transaction Agreement—Conditions to Closing of the Business Combination " for additional information.

The exercise of discretion by AHPAC's directors and officers in agreeing to changes to the terms of or waivers of closing conditions in the Transaction Agreement may result in a conflict of interest when determining whether such changes to the terms of the Transaction Agreement or waivers of conditions are appropriate and in the best interests of AHPAC's shareholders.

        In the period leading up to the consummation of the business combination, other events may occur that, pursuant to the Transaction Agreement, would require AHPAC to agree to amend the Transaction Agreement, to consent to certain actions or to waive rights that it is entitled to under those agreements. Such events could arise because of changes in the course of Envigo's business, a request by Envigo or Envigo to undertake actions that would otherwise be prohibited by the terms of the Transaction Agreement or the occurrence of other events that would have a material adverse effect on Envigo's business and would entitle AHPAC to terminate the Transaction Agreement. In any of such

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circumstances, it would be in the discretion of AHPAC, acting through the AHPAC Board, to grant its consent or waive its rights. The existence of the financial and personal interests of the directors described elsewhere in this proxy statement/prospectus may result in a conflict of interest on the part of one or more of the directors between what he or she may believe is best for AHPAC and AHPAC's shareholders and what he or she may believe is best for himself or herself or his or her affiliates in determining whether or not to take the requested action. As of the date of this proxy statement/prospectus, AHPAC does not believe there will be any changes or waivers that AHPAC's directors and officers would be likely to make after shareholder approval of the business combination has been obtained. While certain changes could be made without further shareholder approval, if there is a change to the terms of the business combination that would have a material impact on the shareholders, AHPAC will be required to circulate a new or amended proxy statement/prospectus or supplement thereto and resolicit the vote of AHPAC's shareholders with respect to the Business Combination Proposal.

AHPAC will incur significant transaction and transition costs in connection with the business combination.

        AHPAC has incurred and expects to incur significant, non-recurring costs in connection with consummating the business combination and operating as a public company following the consummation of the business combination. AHPAC may incur additional costs to retain key employees. All expenses incurred in connection with the Transaction Agreement and the transactions contemplated thereby (including the business combination), including all legal, accounting, consulting, investment banking and other fees, expenses and costs, will be for the account of the party incurring such fees, expenses and costs.

        AHPAC's transaction expenses as a result of the business combination are currently estimated at approximately $17 million.

If AHPAC is unable to complete an initial business combination, public shareholders may receive only approximately $10.00 per share on the liquidation of the trust account (or less than $10.00 per share in certain circumstances where a third party brings a claim against us that the sponsor is unable to indemnify), and AHPAC's warrants will expire worthless.

        If AHPAC is unable to complete an initial business combination by October 14, 2018, public shareholders may receive only approximately $10.00 per share on the liquidation of the trust account (or less than $10.00 per share in certain circumstances where a third-party brings a claim against us that the sponsor unable to indemnify (as described herein)) and AHPAC's warrants will expire worthless.

If third parties bring claims against AHPAC, the proceeds held in the trust account could be reduced and the per-share redemption amount received by shareholders may be less than $10.00 per share.

        AHPAC's placing of funds in the trust account may not protect those funds from third-party claims against it. Although AHPAC will seek to have all vendors, service providers (other than AHPAC's independent auditors), prospective target businesses or other entities with which AHPAC does business execute agreements with it waiving any right, title, interest or claim of any kind in or to any funds held in the trust account for the benefit of public shareholders, such parties may not execute such agreements, or even if they execute such agreements they may not be prevented from bringing claims against the trust account, including, but not limited to, fraudulent inducement, breach of fiduciary responsibility or other similar claims, as well as claims challenging the enforceability of the waiver, in each case in order to gain advantage with respect to a claim against AHPAC's assets, including the funds held in the trust account. If any third party refuses to execute an agreement waiving such claims to the funds held in the trust account, AHPAC's management will perform an analysis of the alternatives available to it and will only enter into an agreement with a third-party that has not

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executed a waiver if management believes that such third party's engagement would be significantly more beneficial to it than any alternative.

        Examples of possible instances where AHPAC may engage a third party that refuses to execute a waiver include the engagement of a third party consultant whose particular expertise or skills are believed by management to be significantly superior to those of other consultants that would agree to execute a waiver or in cases where management is unable to find a service provider willing to execute a waiver. In addition, there is no guarantee that such entities will agree to waive any claims they may have in the future as a result of, or arising out of, any negotiations, contracts or agreements with AHPAC and will not seek recourse against the trust account for any reason. Upon redemption of public shares, if AHPAC is unable to complete the business combination within the prescribed timeframe, or upon the exercise of a redemption right in connection with the business combination, AHPAC will be required to provide for payment of claims of creditors that were not waived that may be brought against it within the ten years following redemption. Accordingly, the per-share redemption amount received by public shareholders could be less than the $10.00 per share initially held in the trust account, due to claims of such creditors. The sponsor has agreed that it will be liable to us if and to the extent any claims by a vendor for services rendered or products sold to AHPAC, or a prospective target business with which AHPAC has discussed entering into a transaction agreement, reduce the amount of funds in the trust account to below (i) $10.00 per public share or (ii) such lesser amount per public share held in the trust account as of the date of the liquidation of the trust account due to reductions in the value of the trust assets, in each case net of the interest which may be withdrawn to pay taxes, except as to any claims by a third party who executed a waiver of any and all rights to seek access to the trust account and except as to any claims under indemnity of the underwriters of the IPO against certain liabilities, including liabilities under the Securities Act. Moreover, in the event that an executed waiver is deemed to be unenforceable against a third party, the sponsor will not be responsible to the extent of any liability for such third party claims. AHPAC has not independently verified whether the sponsor has sufficient funds to satisfy its indemnity obligations and AHPAC has not asked the sponsor to reserve for such indemnification obligations.

AHPAC's directors may decide not to enforce the indemnification obligations of the sponsor, resulting in a reduction in the amount of funds in the trust account available for distribution to public shareholders.

        In the event that the proceeds in the trust account are reduced below the lesser of (i) $10.00 per share and (ii) the actual amount per share held in the trust account as of the date of the liquidation of the trust account if less than $10.00 per share due to reductions in the value of the trust assets, in each case less taxes payable, and the sponsor asserts that it is unable to satisfy his obligations or that he has no indemnification obligations related to a particular claim, AHPAC's independent directors would determine whether to take legal action against The sponsor to enforce its indemnification obligations. While AHPAC currently expects that its independent directors would take legal action on AHPAC's behalf against the sponsor to enforce its indemnification obligations to us, it is possible that AHPAC's independent directors in exercising their business judgment and subject to their fiduciary duties may choose not to do so in any particular instance. If AHPAC's independent directors choose not to enforce these indemnification obligations, the amount of funds in the trust account available for distribution to public shareholders may be reduced below $10.00 per share.

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If, before distributing the proceeds in the trust account to public shareholders, AHPAC files a bankruptcy petition or an involuntary bankruptcy petition is filed against AHPAC that is not dismissed, the claims of creditors in such proceeding may have priority over the claims of AHPAC's shareholders and the per-share amount that would otherwise be received by AHPAC's shareholders in connection with AHPAC's liquidation may be reduced.

        If, before distributing the proceeds in the trust account to public shareholders, AHPAC files a bankruptcy petition or an involuntary bankruptcy petition is filed against AHPAC that is not dismissed, the proceeds held in the trust account could be subject to applicable bankruptcy law, and may be included in AHPAC's bankruptcy estate and subject to the claims of third parties with priority over the claims of AHPAC's shareholders. To the extent any bankruptcy claims deplete the trust account, the per-share amount that would otherwise be received by AHPAC's shareholders in connection with AHPAC's liquidation may be reduced.

If AHPAC's due diligence investigation of Envigo was inadequate, then shareholders of AHPAC following the business combination could lose some or all of their investment.

        Even though AHPAC conducted a due diligence investigation of Envigo, AHPAC cannot be sure that this diligence uncovered all material issues that may be present inside Envigo or its business, or that it would be possible to uncover all material issues through a customary amount of due diligence, or that factors outside of Envigo and its business and outside of its control will not later arise.

Following the consummation of the business combination, ENVG's only significant asset will be its ownership interest in Envigo and such ownership may not be sufficiently profitable or valuable to enable ENVG to pay any dividends on ENVG Class A common stock or satisfy ENVG's other financial obligations, including its obligations under the Tax Receivable Agreement.

        Following the consummation of the business combination, ENVG will have no direct operations and no significant assets other than its ownership interest in Envigo. The initial shareholders, the Selling Equityholders that receive ENVG common stock in the business combination, and directors and officers of Envigo and its affiliates will become shareholders of AHPAC at that time. ENVG will depend on Envigo for distributions, loans and other payments to generate the funds necessary to meet its financial obligations, including its expenses as a publicly traded company, to pay any dividends with respect to ENVG Class A common stock, and to satisfy its obligations under the Tax Receivable Agreement. The financial condition and operating requirements of Envigo may limit ENVG's ability to obtain cash from Envigo. The earnings from, or other available assets of, Envigo may not be sufficient to pay dividends or make distributions or loans to enable ENVG to pay any dividends on the common stock or satisfy its other financial obligations, including its obligations under the Tax Receivable Agreement.

        In addition, payments under the Tax Receivable Agreement are not expressly permitted under Envigo's existing credit facilities and therefore would be required to comply with applicable covenants contained in each applicable credit facility in order to be paid. In accordance with the terms of the Tax Receivable Agreement, if a payment otherwise required under the Tax Receivable Agreement is not permitted by the terms of then outstanding indebtedness for borrowed money, any payment obligation under the Tax Receivable Agreement will be deferred and accrue interest at LIBOR plus 500 basis points from the date that such payment originally became due and payable through the actual payment date.

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We will be required to pay Selling Equityholders for a significant portion of the tax benefit relating to the utilization of certain net operating losses available to be carried forward after the business combination and imputed interest deductions arising from the payments under the Tax Receivable Agreement. In certain instances, we may be required to make payments that exceed, and may be payable years in advance of, the actual realization of future tax benefits, if any.

        At the closing of the business combination, ENVG will enter into a Tax Receivable Agreement with Envigo Holdings, Inc. and the shareholder representative on behalf of the Selling Equityholders. The Tax Receivable Agreement will generally provide for future payments by ENVG to the Selling Equityholders related to 85% of the net cash savings, if any, in U.S. federal, state and local and U.K. income tax that ENVG and its subsidiaries actually realizes (or is deemed to realize in certain circumstances) in periods after the consummation of the business combination as a result of (i) the utilization of net operating losses available to be carried forward as of the consummation of the business combination and (ii) imputed interest deductions arising from payments under the Tax Receivable Agreement. Although the amount and timing of any payments under the Tax Receivable Agreement will vary depending upon a number of factors, including the amount and timing of ENVG's income, AHPAC expects that the payments that ENVG may make thereunder could be substantial. Under certain circumstances, ENVG's obligations under the Tax Receivable Agreement may be accelerated as specified therein.

        As a result of the foregoing, (i) ENVG could be required to make payments under the Tax Receivable Agreement that are greater than or less than the specified percentage of the actual tax savings ENVG realizes in respect of the tax attributes subject to the agreements and (ii) ENVG may be required to make an immediate lump sum payment equal to the present value of the anticipated future tax savings, which payment may be made years in advance of the actual realization of such future benefits, if any of such benefits are ever realized. In these situations, ENVG's obligations under the Tax Receivable Agreement could have a negative impact on ENVG's liquidity and could have the effect of delaying, deferring or preventing certain mergers, asset sales, other forms of business combinations or other changes of control. There can be no assurance that ENVG will be able to finance its obligations under the Tax Receivable Agreement in a manner that does not adversely affect its working capital and growth requirements.

        See the section titled " AHPAC's Management's Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources—Tax Receivable Agreement " beginning on page 175 of this proxy statement/prospectus for more information.

Subsequent to the completion of the business combination, ENVG may be required to take write-downs or write-offs, restructuring and impairment or other charges that could have a significant negative effect on ENVG's financial condition, results of operations and ENVG's stock price, which could cause you to lose some or all of your investment.

        Although AHPAC has conducted due diligence on Envigo, ENVG cannot assure you that this diligence will surface all material issues that may be present in Envigo's business, that it would be possible to uncover all material issues through a customary amount of due diligence, or that factors outside of Envigo's business and outside of ENVG and Envigo's control will not later arise. As a result of these factors, ENVG may be forced to later write-down or write-off assets, restructure operations, or incur impairment or other charges that could result in losses. Even if AHPAC's due diligence successfully identifies certain risks, unexpected risks may arise and previously known risks may materialize in a manner not consistent with AHPAC's preliminary risk analysis. Even though these charges may be non-cash items and not have an immediate impact on ENVG's liquidity, the fact that ENVG charges of this nature could contribute to negative market perceptions about ENVG or its securities. Accordingly, any of AHPAC's shareholders who choose to remain stockholders of ENVG following the business combination could suffer a reduction in the value of their shares. Such

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stockholders are unlikely to have a remedy for such reduction in value unless they are able to successfully claim that the reduction was due to the breach by AHPAC's officers or fiduciary duty owed to them, or if they are able to successfully bring a private claim under securities laws that this proxy statement/prospectus relating to the business combination contained an actionable material misstatement or material omission.

AHPAC has no operating or financial history and AHPAC's results of operations may differ significantly from the unaudited pro forma financial data included in this proxy statement/prospectus.

        AHPAC is a blank check company and AHPAC has no operating history and no revenues. This proxy statement/prospectus includes unaudited pro forma condensed combined financial statements for AHPAC. The unaudited pro forma condensed combined statement of operations of AHPAC combines the historical audited results of operations of AHPAC for the period ended December 31, 2016, with the historical audited results of operations of Envigo for the year ended December 31, 2016, and gives pro forma effect to the business combination as if it had been consummated on January 1, 2016. The unaudited pro forma condensed combined balance sheet of AHPAC combines the historical balance sheets of AHPAC as of September 30, 2017 and of Envigo as of September 30, 2017 and gives pro forma effect to the business combination as if it had been consummated on September 30, 2017.

        The unaudited pro forma condensed combined financial statements are presented for illustrative purposes only, are based on certain assumptions, address a hypothetical situation and reflect limited historical financial data. Therefore, the unaudited pro forma condensed combined financial statements are not necessarily indicative of the results of operations and financial position that would have been achieved had the business combination been consummated on the dates indicated above, or the future consolidated results of operations or financial position of AHPAC. Accordingly, AHPAC's business, assets, cash flows, results of operations and financial condition may differ significantly from those indicated by the unaudited pro forma condensed combined financial statements included in this document. For more information, please see the section entitled " Unaudited Pro Forma Condensed Combined Financial Information ."

Unanticipated changes in effective tax rates or adverse outcomes resulting from examination of ENVG's income or other tax returns could adversely affect ENVG's financial condition and results of operations.

        ENVG will be subject to income taxes in the United States, and ENVG's domestic tax liabilities will be subject to the allocation of expenses in differing jurisdictions. ENVG's future effective tax rates could be subject to volatility or adversely affected by a number of factors, including:

•

changes in the valuation of ENVG's deferred tax assets and liabilities;



•

expected timing and amount of the release of any tax valuation allowances;



•

tax effects of stock-based compensation;



•

costs related to intercompany restructurings;



•

changes in tax laws, regulations or interpretations thereof; and



•

lower than anticipated future earnings in jurisdictions where ENVG has lower statutory tax rates and higher than anticipated future earnings in jurisdictions where ENVG has higher statutory tax rates.

        In addition, ENVG may be subject to audits of ENVG's income, sales and other taxes by U.S. federal, state, local and non-U.S. taxing authorities. Outcomes from these audits could have an adverse effect on ENVG's financial condition and results of operations.

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AHPAC may be a PFIC, which could result in adverse United States federal income tax consequences to U.S. investors.

        If AHPAC is a PFIC for any taxable year (or portion thereof) that is included in the holding period of a U.S. holder of AHPAC Class A ordinary shares or warrants, the U.S. holder may be subject to adverse U.S. federal income tax consequences and may be subject to additional reporting requirements. Based on the composition of AHPAC's income and assets, AHPAC believes it was a PFIC for its taxable years ended December 31, 2016 and December 31, 2017 and that it will be treated as a PFlC for its current taxable year which will end as a result of the domestication. U.S. holders should consult their tax advisors regarding the possible application of the PFIC rules. For a more detailed explanation of the tax consequences of PFIC classification to U.S. holders, see " Material U.S. Federal Income Tax Considerations — U.S. Holders — Passive Foreign Investment Company Rules ."

A market for ENVG's securities may not continue, which would adversely affect the liquidity and price of ENVG's securities.

        Following the business combination, the price of ENVG's securities may fluctuate significantly due to the market's reaction to the business combination and general market and economic conditions. An active trading market for ENVG's securities following the business combination may never develop or, if developed, it may not be sustained. In addition, the price of ENVG's securities after the business combination can vary due to general economic conditions and forecasts, ENVG's general business condition and the release of ENVG's financial reports. Additionally, if ENVG's securities are not listed on, or become delisted from, NASDAQ for any reason, and are quoted on the OTC Bulletin Board, an inter-dealer automated quotation system for equity securities that is not a national securities exchange, the liquidity and price of ENVG's securities may be more limited than if ENVG was quoted or listed on NASDAQ or another national securities exchange. You may be unable to sell your securities unless a market can be established or sustained.

If the business combination's benefits do not meet the expectations of investors, shareholders or financial analysts, the market price of AHPAC's securities may decline.

        If the benefits of the business combination do not meet the expectations of investors, shareholders or securities analysts, the market price of AHPAC's securities prior to the consummation of the business combination may decline. The market values of AHPAC's securities at the time of the business combination may vary significantly from their prices on the date the Transaction Agreement was executed, the date of this proxy statement/prospectus, or the date on which AHPAC's shareholders vote on the business combination.

        In addition, following the business combination, fluctuations in the price of AHPAC's securities could contribute to the loss of all or part of your investment. Immediately prior to the business combination, there has not been a public market for Envigo's stock and trading in AHPAC Class A ordinary shares has not been active. Accordingly, the valuation ascribed to Envigo and AHPAC Class A ordinary shares in the business combination may not be indicative of the price that will prevail in the trading market following the business combination. If an active market for AHPAC's securities develops and continues, the trading price of AHPAC's securities following the business combination could be volatile and subject to wide fluctuations in response to various factors, some of which are beyond its control. Any of the factors listed below could have a material adverse effect on your investment in AHPAC's securities and AHPAC's securities may trade at prices significantly below the price you paid for them. In such circumstances, the trading price of AHPAC's securities may not recover and may experience a further decline.

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        Factors affecting the trading price of ENVG's securities following the business combination may include:

•

actual or anticipated fluctuations in ENVG's quarterly financial results or the quarterly financial results of companies perceived to be similar to us;



•

changes in the market's expectations about ENVG's operating results;



•

the public's reaction to ENVG's press releases, ENVG's other public announcements and ENVG's filings with the SEC;



•

speculation in the press or investment community;



•

success of competitors;



•

the operating results failing to meet the expectation of securities analysts or investors in a particular period;



•

changes in financial estimates and recommendations by securities analysts concerning ENVG or the market in general;



•

operating and stock price performance of other companies that investors deem comparable to ENVG;



•

ENVG's ability to market new and enhanced products on a timely basis;



•

changes in laws and regulations affecting ENVG's business;



•

commencement of, or involvement in, litigation involving ENVG;



•

changes in ENVG's capital structure, such as future issuances of securities or the incurrence of additional debt;



•

the volume of ENVG Class A common stock available for public sale;



•

any major change in ENVG's Board or management;



•

sales of substantial amounts of ENVG Class A common stock by ENVG's directors, officers or significant shareholders or the perception that such sales could occur;



•

general economic and political conditions such as recessions, interest rates, fuel prices, international currency fluctuations and acts of war or terrorism; and



•

other risk factors listed under "Risk Factors" starting on page 37.

        Broad market and industry factors may materially harm the market price of ENVG's securities irrespective of ENVG's operating performance. The stock market in general and NASDAQ have experienced price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of the particular companies affected. The trading prices and valuations of these stocks, and of ENVG's securities, may not be predictable. A loss of investor confidence in the market for the stocks of other companies which investors perceive to be similar to ENVG could depress ENVG's stock price regardless of ENVG's business, prospects, financial conditions or results of operations. A decline in the market price of ENVG's securities also could adversely affect ENVG's ability to issue additional securities and ENVG's ability to obtain additional financing in the future.

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        In the past, securities class action litigation has often been initiated against companies following periods of volatility in their stock price. This type of litigation could result in substantial costs and divert AHPAC's management's attention and resources, and could also require us to make substantial payments to satisfy judgments or to settle litigation.

ENVG's quarterly operating results may fluctuate significantly and could fall below the expectations of securities analysts and investors due to seasonality and other factors, some of which are beyond ENVG's control, resulting in a decline in ENVG's stock price.

        ENVG's quarterly operating results may fluctuate significantly because of several factors, including:

•

labor availability and costs for hourly and management personnel;



•

profitability of ENVG's products, especially in new markets and due to seasonal fluctuations;



•

changes in interest or exchange rates;



•

impairment of long-lived assets;



•

macroeconomic conditions, both nationally and locally;



•

negative publicity relating to products we serve;



•

changes in consumer preferences and competitive conditions;



•

expansion to new markets; and



•

fluctuations in commodity prices.

If, following the business combination, securities or industry analysts do not publish or cease publishing research or reports about ENVG, its business, or its market, or if they change their recommendations regarding ENVG Class A common stock adversely, then the price and trading volume of ENVG Class A common stock could decline.

        The trading market for ENVG Class A common stock will be influenced by the research and reports that industry or securities analysts may publish about us, ENVG's business, ENVG's market, or ENVG's competitors. Securities and industry analysts do not currently, and may never, publish research on AHPAC or ENVG. If no securities or industry analysts commence coverage of ENVG, ENVG's stock price and trading volume would likely be negatively impacted. If any of the analysts who may cover ENVG change their recommendation regarding ENVG's stock adversely, or provide more favorable relative recommendations about ENVG's competitors, the price of ENVG Class A common stock would likely decline. If any analyst who may cover AHPAC were to cease coverage of ENVG or fail to regularly publish reports on it, we could lose visibility in the financial markets, which could cause ENVG's stock price or trading volume to decline.

ENVG may be unable to obtain additional financing to fund its operations or growth.

        ENVG may require additional financing to fund its operations or growth. The failure to secure additional financing could have a material adverse effect on the continued development or growth of ENVG. None of AHPAC's officers, directors or shareholders is required to provide any financing to us in connection with or after the business combination.

Some of Envigo's existing debt will incur increased interest costs beginning in April 2018 if it is not refinanced before that time.

        Envigo's current first lien and second lien term debt will see an increase in interest rates in April 2018 if that debt is not refinanced before then. Specifically, the First Lien Credit Agreement, which

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currently carries an interest rate of LIBOR plus 2.5%, would increase to LIBOR plus 5.75% and the Second Lien Credit Agreement, which currently carries an interest rate of LIBOR plus 2.5%, would increase to LIBOR plus 7.75%.

Changes in laws, regulations or rules, or a failure to comply with any laws, regulations or rules, may adversely affect ENVG's business, investments and results of operations.

        ENVG will be subject to laws, regulations and rules enacted by national, regional and local governments and NASDAQ. In particular, ENVG will be required to comply with certain SEC, NASDAQ and other legal or regulatory requirements. Compliance with, and monitoring of, applicable laws, regulations and rules may be difficult, time consuming and costly. Those laws, regulations or rules and their interpretation and application may also change from time to time and those changes could have a material adverse effect on ENVG's business, investments and results of operations. In addition, a failure to comply with applicable laws, regulations or rules, as interpreted and applied, could have a material adverse effect on ENVG's business and results of operations.

The Sponsor, Jermyn Street Associates LLC and Savanna Holdings LLC will have significant influence over ENVG after completion of the business combination.

        Upon completion of the business combination, the sponsor, Jermyn Street Associates LLC and Savanna Holdings LLC will beneficially own approximately 5.6%, 16.9% and 9.9%, respectively, of ENVG Class A common stock. As long as the sponsor, Jermyn Street Associates LLC or Savanna Holdings LLC own or control a significant percentage of ENVG's outstanding voting power, they will have the ability to significantly influence all corporate actions requiring shareholder approval, including the election and removal of directors and the size of ENVG's Board, any amendment to ENVG's organizational documents, or the approval of any merger or other significant corporate transaction, including a sale of substantially all of ENVG's assets.

        The sponsor, Jermyn Street Associates LLC or Savanna Holdings LLC's interests may not align with the interests of ENVG's other shareholders. The sponsor, Jermyn Street Associates LLC and Savanna Holdings LLC are each in the business of making investments in companies and may acquire and hold interests in businesses that compete directly or indirectly with ENVG. The sponsor, Jermyn Street Associates LLC or Savanna Holdings LLC may also pursue acquisition opportunities that may be complementary to ENVG's business, and, as a result, those acquisition opportunities may not be available to us. In addition, ENVG's proposed certificate and proposed bylaws provide that the ENVG Sponsors may engage in competitive businesses and renounce certain corporate opportunities offered to the ENVG Sponsors or any of their managers, officers, directors, agents, stockholders, members, partners, affiliates and subsidiaries (other than ENVG and its subsidiaries) that are not expressly offered to them in their capacities as directors or officers of ENVG. The proposed certificate and proposed bylaws also provide that the ENVG Sponsors or any of their managers, officers, directors, agents, stockholders, members, partners, affiliates and subsidiaries (other than ENVG and its subsidiaries), do not have any fiduciary duty to refrain from engaging directly or indirectly in the same or similar business activities or lines of business as ENVG or any of its subsidiaries.

Registration of the ENVG Class A common stock underlying the warrants may not be in place when an investor desires to exercise warrants, thus precluding such investor from being able to exercise its warrants except on a cashless basis and potentially causing such warrants to expire worthless.

        AHPAC has not registered the ENVG Class A common stock issuable upon exercise of the warrants under the Securities Act or any state securities laws at this time. However, under the terms of the warrant agreement, AHPAC has agreed, as soon as practicable, but in no event later than 15 business days after the consummation of the business combination, to use its best efforts to file a registration statement under the Securities Act covering such shares and maintain a current prospectus

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relating to the ENVG Class A common stock issuable upon exercise of the warrants, until the expiration of the warrants in accordance with the provisions of the warrant agreement. AHPAC cannot assure you that it will be able to do so if, for example, any facts or events arise which represent a fundamental change in the information set forth in such registration statement or prospectus, the financial statements contained or incorporated by reference therein are not current or correct or the SEC issues a stop order. If the shares issuable upon exercise of the warrants are not registered under the Securities Act, ENVG will be required to permit holders to exercise their warrants on a cashless basis. However, no warrant will be exercisable for cash or on a cashless basis, and we will not be obligated to issue any shares to holders seeking to exercise their warrants, unless the issuance of the shares upon such exercise is registered or qualified under the securities laws of the state of the exercising holder or an exemption is available. Notwithstanding the above, if ENVG Class A common stock are at the time of any exercise of a warrant not listed on a national securities exchange such that it satisfies the definition of a "covered security" under Section 18(b)(1) of the Securities Act, we may, at ENVG's option, require holders of warrants who exercise their warrants to do so a "cashless basis" in accordance with Section 3(a)(9) of the Securities Act and, in the event we so elect, we will not be required to file or maintain in effect a registration statement, but we will use its best efforts to register or qualify the shares under applicable blue sky laws to the extent an exemption is not available. In no event will we be required to net cash settle any warrant, or issue securities or other compensation in exchange for the warrants in the event that we are unable to register or qualify the shares underlying the warrants under applicable state securities laws. If the issuance of the shares upon exercise of the warrants is not so registered or qualified or exempt from registration or qualification, the holder of such warrant shall not be entitled to exercise such warrant and such warrant may have no value and expire worthless. In such event, holders who acquired their warrants as part of a purchase of units will have paid the full unit purchase price solely for the ENVG Class A common stock included in the units. If and when the warrants become redeemable by us, ENVG may exercise its redemption right even If ENVG is unable to register or qualify the underlying ENVG Class A common stock for sale under all applicable state securities laws.

ENVG may amend the terms of the warrants in a manner that may be adverse to holders with the approval by the holders of at least 65% of the then-outstanding warrants.

        ENVG warrants will be issued in registered form under a warrant agreement between Continental Stock Transfer & Trust Company, as warrant agent, and AHPAC. The warrant agreement provides that the terms of the warrants may be amended without the consent of any holder to cure any ambiguity or correct any defective provision, but requires the approval by the holders of at least 65% of the then-outstanding public warrants to make any change that adversely affects the interests of the registered holders. Accordingly, AHPAC may amend the terms of the warrants in a manner adverse to a holder if holders of at least 65% of the then-outstanding public warrants approve of such amendment. Although ENVG's ability to amend the terms of the warrants with the consent of at least 65% of the then-outstanding public warrants is unlimited, examples of such amendments could be amendments to, among other things, increase the exercise price of the warrants, shorten the exercise period or decrease the number of shares of ENVG Class A common stock purchasable upon exercise of a warrant.

ENVG may redeem your unexpired warrants prior to their exercise at a time that is disadvantageous to you, thereby making your warrants worthless.

        ENVG will have the ability to redeem outstanding warrants at any time after they become exercisable and prior to their expiration, at a price of $0.01 per warrant, provided that the closing price of ENVG Class A common stock equals or exceeds $24.00 per share (as adjusted for share splits, share capitalizations, reorganizations, recapitalizations and the like) for any 20 trading days within a 30 trading-day period ending on the third trading day prior to proper notice of such redemption provided

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that on the date we give notice of redemption. If and when the warrants become redeemable, ENVG may exercise its redemption right even if it is unable to register or qualify the underlying securities for sale under all applicable state securities laws. Redemption of the outstanding warrants could force you to (i) exercise your warrants and pay the exercise price therefor at a time when it may be disadvantageous for you to do so, (ii) sell your warrants at the then-current market price when you might otherwise wish to hold your warrants or (iii) accept the nominal redemption price which, at the time the outstanding warrants are called for redemption, is likely to be substantially less than the market value of your warrants. None of the private placement warrants will be redeemable by us so long as they are held by their initial purchasers or their permitted transferees.

The exercise of outstanding warrants would increase the number of shares eligible for future resale in the public market and result in dilution to shareholders.

        AHPAC issued warrants to purchase 15,500,000 AHPAC Class A ordinary shares as part of the IPO and prior to the IPO, AHPAC issued private placement warrants to the initial shareholders to purchase 8,200,000 AHPAC Class A ordinary shares, in each case at $11.50 per share. In addition, prior to consummating an initial business combination, subject to the terms of the Transaction Agreement, AHPAC may issue additional securities in the equity financing so long as they do not participate in any manner in the trust account or vote as a class with the common stock on a business combination. The shares of ENVG Class A common stock issued in the equity financing (if any) and additional shares of ENVG Class A common stock issued upon exercise of AHPAC's warrants will result in dilution to the then existing holders of AHPAC Class A ordinary shares and increase the number of shares eligible for resale in the public market. Sales of substantial numbers of such shares in the public market could adversely affect the market price of AHPAC Class A ordinary shares and ENVG Class A common stock.

Because AHPAC is incorporated under the laws of the Cayman Islands, you may face difficulties in protecting your interests, and your ability to protect your rights through the U.S. Federal courts may be limited.

        AHPAC is an exempted company incorporated under the laws of the Cayman Islands. As a result, it may be difficult for investors to effect service of process within the United States upon AHPAC's directors or executive officers, or enforce judgments obtained in the United States courts against AHPAC's directors or officers.

        AHPAC corporate affairs are governed by AHPAC's amended and restated memorandum and articles of association, the Companies Law (as the same may be supplemented or amended from time to time) and the common law of the Cayman Islands. AHPAC will also be subject to the federal securities laws of the United States. The rights of shareholders to take action against the directors, actions by minority shareholders and the fiduciary responsibilities of AHPAC's directors to us under Cayman Islands law are to a large extent governed by the common law of the Cayman Islands. The common law of the Cayman Islands is derived in part from comparatively limited judicial precedent in the Cayman Islands as well as from English common law, the decisions of whose courts are of persuasive authority, but are not binding on a court in the Cayman Islands. The rights of AHPAC's shareholders and the fiduciary responsibilities of AHPAC's directors under Cayman Islands law are different from what they would be under statutes or judicial precedent in some jurisdictions in the United States. In particular, the Cayman Islands has a different body of securities laws as compared to the United States, and certain states, such as Delaware, may have more fully developed and judicially interpreted bodies of corporate law. In addition, Cayman Islands companies may not have standing to initiate a shareholders derivative action in a Federal court of the United States.

        AHPAC has been advised by AHPAC Cayman Islands legal counsel that the courts of the Cayman Islands are unlikely (i) to recognize or enforce against us judgments of courts of the United States predicated upon the civil liability provisions of the federal securities laws of the United States or any

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state; and (ii) in original actions brought in the Cayman Islands, to impose liabilities against us predicated upon the civil liability provisions of the federal securities laws of the United States or any state, so far as the liabilities imposed by those provisions are penal in nature. In those circumstances, although there is no statutory enforcement in the Cayman Islands of judgments obtained in the United States, the courts of the Cayman Islands will recognize and enforce a foreign money judgment of a foreign court of competent jurisdiction without retrial on the merits based on the principle that a judgment of a competent foreign court imposes upon the judgment debtor an obligation to pay the sum for which judgment has been given provided certain conditions are met. For a foreign judgment to be enforced in the Cayman Islands, such judgment must be final and conclusive and for a liquidated sum, and must not be in respect of taxes or a fine or penalty, inconsistent with a Cayman Islands judgment in respect of the same matter, impeachable on the grounds of fraud or obtained in a manner, or be of a kind the enforcement of which is, contrary to natural justice or the public policy of the Cayman Islands (awards of punitive or multiple damages may well be held to be contrary to public policy). A Cayman Islands Court may stay enforcement proceedings if concurrent proceedings are being brought elsewhere.

        As a result of all of the above, public shareholders may have more difficulty in protecting their interests in the face of actions taken by management, members of the board of directors or controlling shareholders than they would as public shareholders of a United States company.

Provisions in ENVG's proposed charter may inhibit a takeover of ENVG, which could limit the price investors might be willing to pay in the future for ENVG Class A common stock and could entrench management.

        ENVG's proposed certificate of incorporation contains provisions that may discourage unsolicited takeover proposals that shareholders may consider to be in their best interests. These provisions include a staggered board of directors and the ability of the board of directors to designate the terms of and issue new series of preferred shares, which may make more difficult the removal of management and may discourage transactions that otherwise could involve payment of a premium over prevailing market prices for AHPAC's securities.

The JOBS Act permits "emerging growth companies" like us to take advantage of certain exemptions from various reporting requirements applicable to other public companies that are not emerging growth companies.

        AHPAC qualifies as an "emerging growth company" as defined in Section 2(a)(19) of the Securities Act, as modified by the Jumpstart Our Business Startups Act of 2012, which we refer to as the "JOBS Act." As such, following the consummation of the business combination, ENVG will take advantage of certain exemptions from various reporting requirements applicable to other public companies that are not emerging growth companies for as long as it continues to be an emerging growth company, including (i) the exemption from the auditor attestation requirements with respect to internal control over financial reporting under Section 404 of the Sarbanes-Oxley Act, (ii) the exemptions from say-on-pay, say-on-frequency and say-on-golden parachute voting requirements and (iii) reduced disclosure obligations regarding executive compensation in its periodic reports and proxy statements. As a result, ENVG's stockholders may not have access to certain information they deem important. ENVG will remain an emerging growth company until the earliest of (i) the last day of the fiscal year (a) following October 14, 2021, the fifth anniversary of the IPO, (b) in which ENVG has total annual gross revenue of at least $1.0 billion or (c) in which ENVG is deemed to be a large accelerated filer, which means the market value of ENVG Class A common stock that are held by non-affiliates exceeds $700 million as of the last business day of ENVG's prior second fiscal quarter, and (ii) the date on which ENVG has issued more than $1.0 billion in non-convertible debt during the prior three-year period.

        In addition, Section 107 of the JOBS Act also provides that an emerging growth company can take advantage of the exemption from complying with new or revised accounting standards provided in

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Section 7(a)(2)(B) of the Securities Act as long as ENVG is an emerging growth company. An emerging growth company can therefore delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. The JOBS Act provides that a company can elect to opt out of the extended transition period and comply with the requirements that apply to non-emerging growth companies, but any such election to opt out is irrevocable. ENVG has elected not to opt out of such extended transition period, which means that when a standard is issued or revised and it has different application dates for public or private companies, we, as an emerging growth company, can adopt the new or revised standard at the time private companies adopt the new or revised standard. This may make comparison of ENVG's financial statements with another public company which is neither an emerging growth company nor an emerging growth company which has opted out of using the extended transition period difficult or impossible because of the potential differences in accounting standards used.

        AHPAC cannot predict if investors will find ENVG Class A common stock less attractive because ENVG will rely on these exemptions. If some investors find ENVG Class A common stock less attractive as a result, there may be a less active trading market for ENVG Class A common stock and ENVG's stock price may be more volatile.

Risks Related to the Redemption

You must tender your AHPAC Class A ordinary shares in order to validly seek redemption at the annual general meeting.

        In connection with tendering your shares for redemption, you must elect either to physically tender your ordinary share certificates to AHPAC's transfer agent in each case by two business days prior to the consummation of the business combination, or to deliver your ordinary shares to the transfer agent electronically using The Depository Trust Company's DWAC (Deposit/Withdrawal At Custodian) System, which election would likely be determined based on the manner in which you hold your ordinary shares. The requirement for physical or electronic delivery by the business day prior to the consummation of the business combination ensures that a redeeming holder's election to redeem is irrevocable once the business combination is consummated. Any failure to observe these procedures will result in your loss of redemption rights in connection with the vote on the business combination.

AHPAC does not have a specified maximum redemption threshold. The absence of such a redemption threshold may make it possible for us to complete a business combination with which a substantial majority of AHPAC's shareholders do not agree.

        AHPAC's amended and restated memorandum and articles of association does not provide a specified maximum redemption threshold, except that AHPAC will not redeem public shares in an amount that would cause AHPAC net tangible assets to be less than $5,000,001 (as determined in accordance with Rule 3a51-1(g)(1) of the Exchange Act). However, the Transaction Agreement provides the obligations of Envigo to consummate the business combination is conditioned on there being at least $220 million of available funds from the trust account and proceeds from the equity financing (if any), after giving effect to redemptions of public shares. As a result, AHPAC may be able to complete the business combination even though a substantial portion of public shareholders do not agree with the transaction and have redeemed their shares or have entered into privately negotiated agreements to sell their shares to the sponsor, directors or officers or their affiliates. As of the date of this proxy statement/prospectus, no agreements with respect to the private purchase of public shares by AHPAC or the persons described above have been entered into with any such investor or holder. AHPAC will file a Current Report on Form 8-K with the SEC to disclose private arrangements entered into or significant private purchases made by any of the aforementioned persons that would affect the vote on the Business Combination Proposal or other proposals (as described in this proxy statement/prospectus) at the general meeting.

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        In the event the aggregate cash consideration AHPAC would be required to pay for all AHPAC Class A ordinary shares that are validly submitted for redemption plus any amount required to satisfy cash conditions pursuant to the terms of the Transaction Agreement exceeds the aggregate exchange amount of cash available to us, AHPAC may not complete the business combination or redeem any shares, all AHPAC Class A ordinary shares submitted for redemption will be returned to the holders thereof, and AHPAC instead may search for an alternate business combination.

If you or a "group" of shareholders of which you are a part are deemed to hold an aggregate of more than fifteen percent (15%) of the AHPAC Class A ordinary shares issued in the IPO, you (or, if a member of such a group, all of the members of such group in the aggregate) will lose the ability to redeem all such shares in excess of 15% of the AHPAC Class A ordinary shares issued in the IPO.

        A public shareholder, together with any of his, her or its affiliates or any other person with whom it is acting in concert or as a "group" (as defined under Section 13 of the Exchange Act), will be restricted from redeeming in the aggregate his, her or its shares or, if part of such a group, the group's shares, in excess of 15% of the AHPAC Class A ordinary shares included in the units sold in the IPO. In order to determine whether a shareholder is acting in concert or as a group with another shareholder, AHPAC will require each public shareholder seeking to exercise redemption rights to certify to AHPAC whether such shareholder is acting in concert or as a group with any other shareholder. Such certifications, together with other public information relating to stock ownership available to AHPAC at that time, such as Section 13D, Section 13G and Section 16 filings under the Exchange Act, will be the sole basis on which AHPAC makes the above-referenced determination. Your inability to redeem any such excess shares will reduce your influence over AHPAC's ability to consummate the business combination and you could suffer a material loss on your investment in AHPAC if you sell such excess shares in open market transactions. Additionally, you will not receive redemption distributions with respect to such excess shares if AHPAC consummates the business combination. As a result, you will continue to hold that number of shares aggregating to more than 15% of the shares sold in the IPO and, in order to dispose of such excess shares, would be required to sell your stock in open market transactions, potentially at a loss. AHPAC cannot assure you that the value of such excess shares will appreciate over time following the business combination or that the market price of AHPAC Class A ordinary shares will exceed the per-share redemption price. Notwithstanding the foregoing, shareholders may challenge AHPAC's determination as to whether a shareholder is acting in concert or as a group with another shareholder in a court of competent jurisdiction.

        However, AHPAC's shareholders' ability to vote all of their shares (including such excess shares) for or against the business combination is not restricted by this limitation on redemption.

There is no guarantee that a shareholder's decision whether to redeem its shares for a pro rata portion of the trust account will put the shareholder in a better future economic position.

        AHPAC can give no assurance as to the price at which a shareholder may be able to sell its public shares in the future following the completion of the business combination or any alternative business combination. Certain events following the consummation of any initial business combination, including the business combination, may cause an increase in AHPAC share price, and may result in a lower value realized now than a shareholder of AHPAC might realize in the future had the shareholder not redeemed its shares. Similarly, if a shareholder does not redeem its shares, the shareholder will bear the risk of ownership of the public shares after the consummation of any initial business combination, and there can be no assurance that a shareholder can sell its shares in the future for a greater amount than the redemption price set forth in this proxy statement/prospectus. A shareholder should consult the shareholder's own tax and/or financial advisor for assistance on how this may affect his, her or its individual situation.

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Shareholders of AHPAC who wish to redeem their shares for a pro rata portion of the trust account must comply with specific requirements for redemption that may make it more difficult for them to exercise their redemption rights prior to the deadline. If shareholders fail to comply with the redemption requirements specified in this proxy statement/ prospectus, they will not be entitled to redeem their AHPAC Class A ordinary shares for a pro rata portion of the funds held in the trust account.

        Public shareholders who wish to redeem their shares for a pro rata portion of the trust account must, among other things (i) submit a request in writing and (ii) tender their certificates to AHPAC's transfer agent or deliver their shares to the transfer agent electronically through the DWAC system at least two business days prior to the general meeting. In order to obtain a physical stock certificate, a shareholder's broker and/or clearing broker, DTC and AHPAC's transfer agent will need to act to facilitate this request. It is AHPAC's understanding that shareholders should generally allot at least two weeks to obtain physical certificates from the transfer agent. However, because AHPAC does not have any control over this process or over the brokers, which AHPAC refers to as "DTC," it may take significantly longer than two weeks to obtain a physical stock certificate. If it takes longer than anticipated to obtain a physical certificate, shareholders who wish to redeem their shares may be unable to obtain physical certificates by the deadline for exercising their redemption rights and thus will be unable to redeem their shares.

        Shareholders electing to redeem their shares will receive their pro rata portion of the trust account less franchise and income taxes payable, calculated as of two business days prior to the anticipated consummation of the business combination. Please see the section entitled " Annual General Meeting of AHPAC Shareholders—Redemption Rights " for additional information on how to exercise your redemption rights.

If a shareholder fails to receive notice of AHPAC offer to redeem public shares in connection with the business combination, or fails to comply with the procedures for tendering its shares, such shares may not be redeemed.

        If, despite AHPAC compliance with the proxy rules, a shareholder fails to receive AHPAC proxy materials, such shareholder may not become aware of the opportunity to redeem its shares. In addition, the proxy materials that AHPAC is furnishing to holders of public shares in connection with the business combination describes the various procedures that must be complied with in order to validly redeem public shares. In the event that a shareholder fails to comply with these procedures, its shares may not be redeemed.

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ANNUAL GENERAL MEETING OF AHPAC SHAREHOLDERS

        This proxy statement/prospectus is being provided to AHPAC's shareholders as part of a solicitation of proxies by the AHPAC Board for use at the general meeting of AHPAC's shareholders to be held on [     ·     ] 2018, and at any adjournment or postponement thereof. This proxy statement/prospectus contains important information regarding the general meeting, the proposals on which you are being asked to vote and information you may find useful in determining how to vote and voting procedures.

        This proxy statement/prospectus is being first mailed on or about [     ·     ], 2018 to all shareholders of record of AHPAC as of January 16, 2018, the record date for the general meeting. Shareholders of record who owned AHPAC ordinary shares at the close of business on the record date are entitled to receive notice of, attend and vote at the general meeting. On the record date, there were 38,750,000 ordinary shares outstanding.

Date, Time and Place of general meeting

        The general meeting will be held at [     ·     ] Eastern Time on [     ·     ], 2018 at the offices of Weil, Gotshal & Manges, 767 Fifth Avenue, New York NY 10153, or such other date, time and place to which such meeting may be adjourned or postponed, to consider and vote upon the proposals.

Voting Power; Record Date

        As a shareholder of AHPAC, you have a right to vote on the matters presented at the general meeting, which are summarized above and fully set forth in this proxy statement/prospectus. You will be entitled to vote or direct votes to be cast at the general meeting if you owned AHPAC ordinary shares at the close of business on January 16, 2018, which is the record date for the general meeting. You are entitled to one vote for each AHPAC ordinary share that you owned as of the close of business on the record date. If your shares are held in "street name" or are in a margin or similar account, you should contact your broker, bank or other nominee to ensure that votes related to the shares you beneficially own are properly counted. On the record date, there were 38,750,000 AHPAC ordinary shares outstanding, of which 31,000,000 are AHPAC Class A ordinary shares and 7,750,000 are AHPAC Class B ordinary shares held by the initial shareholders.

Proposals at the general meeting

        At the general meeting, AHPAC's shareholders will vote on the following proposals:

1.

Proposal No. 1—The Business Combination Proposal —To consider and vote upon a proposal to approve and adopt the Transaction Agreement and the transactions contemplated thereby, which we refer to as the "Business Combination Proposal";



2.

Proposal No. 2—The Domestication Proposal— To consider and vote upon a proposal to approve by special resolution, assuming the Business Combination Proposal is approved and adopted, the domestication, which we refer to as the "Domestication Proposal";


The Charter Proposals —To consider and vote upon nine separate proposals to approve by special resolution, assuming the Business Combination Proposal is approved and adopted, the following material differences between AHPAC's existing amended and restated memorandum and articles of association and the proposed certificate and the proposed bylaws of ENVG upon the domestication:

3.

Proposal No. 3 —To consider and vote upon an amendment to AHPAC's existing organizational documents to authorize the classification of the Board into three classes of directors, which shall consist of, as nearly as may be possible, one-third of the total number of

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directors on the Board, which will initially be seven (7) and then as may be set by the Board from time to time;

4.

Proposal No. 4 —To consider and vote upon an amendment to AHPAC's existing organizational documents to authorize that directors may only be removed for cause;



5.

Proposal No. 5 —To consider and vote upon an amendment to AHPAC's existing organizational documents to authorize that only the Board, chairperson of the board of directors or chief executive offer may call a meeting of stockholders;



6.

Proposal No. 6 —To consider and vote upon an amendment to AHPAC's existing organizational documents to authorize removal of the ability of stockholders to take action by written consent in lieu of a meeting;



7.

Proposal No. 7 —To consider and vote upon an amendment to AHPAC's existing organizational documents to require the affirmative vote of holders of a majority of the voting power of ENVG's then issued and outstanding shares of stock entitled to amend the proposed certificate;



8.

Proposal No. 8 —To consider and vote upon an amendment to AHPAC's existing organizational documents to authorize the adoption of Delaware as the exclusive forum for certain stockholder litigation;



9.

Proposal No. 9 —To consider and vote upon an amendment to AHPAC's existing organizational documents to authorize ENVG to permit the ENVG Sponsors to engage in competitive businesses and renounce certain corporate opportunities offered to the ENVG Sponsors or any of their managers, officers, directors, agents, stockholders, members, partners, affiliates and subsidiaries (other than ENVG and its subsidiaries) that are not expressly offered to them in their capacities as directors or officers of ENVG;



10.

Proposal No. 10 —To consider and vote upon an amendment to AHPAC's existing organizational documents to approve the authorized number of shares of ENVG common stock contained in the proposed certificate; and



11.

Proposal No. 11 —To consider and vote upon an amendment to AHPAC's existing organizational documents to authorize other changes to the organizational documents resulting from the domestication and business combination, including changing the post-business combination corporate name from "Avista Healthcare Public Acquisition Corp." to "Envigo International Holdings, Inc." and removing certain provisions relating to our status as a blank-check company that will no longer apply upon consummation of the business combination;

We refer to Proposals No. 3-11 collectively as the "Charter Proposals";

12.

Proposal No. 12—The Director Election Proposal —To consider and vote upon a proposal to elect seven directors to serve staggered terms on ENVG's Board of Directors until the 2019, 2020 and 2021 annual meeting of shareholders, respectively, and until their respective successors are duly elected and qualified, which we refer to as the "Director Election Proposal";



13.

Proposal No. 13—The Management Incentive Plan Proposal —To consider and vote on a proposal to approve and adopt, assuming the Charter Proposals, the Domestication Proposal and the Business Combination Proposal are all approved and adopted, 2018 Equity Incentive Plan and the material terms thereunder, which we refer to as the "Management Incentive Plan Proposal". A copy of the 2018 Equity Incentive Plan is attached to the accompanying proxy statement/prospectus as Annex G ;

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14.

Proposal No. 14—The NASDAQ Proposal— To consider and vote upon a proposal to approve, assuming the Charter Proposals, the Domestication Proposal and the Business Combination Proposal are all approved and adopted, for purposes of complying with applicable provisions of NASDAQ Listing Rule 5635, the issuance of more than 20% of AHPAC's issued and outstanding ordinary shares (or issued and outstanding common stock following the domestication) to the Selling Equityholders in connection with the business combination and to participants in the equity financing (if any) that may be deemed a change of control, which we refer to as the "NASDAQ Proposal". and



15.

Proposal No. 15—Adjournment Proposal —To consider and vote upon a proposal to approve the adjournment of the general meeting to a later date or dates, if necessary, to permit further solicitation and vote of proxies in the event that there are insufficient votes for, or otherwise in connection with, the approval of one or more proposals to be submitted for shareholder approval at the general meeting, which we refer to as the "Adjournment Proposal."

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THE AHPAC BOARD UNANIMOUSLY RECOMMENDS THAT YOU VOTE "FOR" EACH OF THESE PROPOSALS.

Vote of AHPAC's Sponsor, Directors and Officers

        In connection with the IPO, the initial shareholders agreed to vote their founder shares and any public shares purchased during or after the IPO in favor of the business combination. Currently, the initial shareholders own approximately 20% of AHPAC's issued and outstanding ordinary shares, including all of the founder shares. These agreements apply to the initial shareholders, including the sponsor, as it relates to the founder shares and the requirement to vote all of the founder shares in favor of the Business Combination Proposal and for all other proposals presented to AHPAC's shareholders in this proxy statement/prospectus.

        The initial shareholders, other current directors and officers have waived any redemption rights, including with respect to AHPAC Class A ordinary shares purchased in the IPO or in the aftermarket, in connection with business combination. The founder shares held by the initial shareholders have no redemption rights upon AHPAC's liquidation and will be worthless if no business combination is effected by us by October 14, 2018. However, the initial shareholders are entitled to redemption rights upon AHPAC's liquidation with respect to any public shares they may own.

Quorum and Required Vote for Proposals for the General Meeting

        The approval of each of the Domestication Proposal and the Charter Proposals requires the affirmative vote of the holders of two-thirds of the ordinary shares represented in person or by proxy and entitled to vote thereon at the general meeting. Accordingly, if an AHPAC shareholder fails to vote by proxy or to vote in person at the general meeting, their shares will not be counted in connection with the determination of whether a valid quorum is established, however, if a valid quorum is otherwise established, such failure to vote will have no effect on the outcome of any vote on the Domestication Proposal or any of the Charter Proposals. Abstentions will be counted in connection with the determination of whether a valid quorum is established and will have the same effect as a vote " AGAINST " the Domestication Proposal and the Charter Proposals.