NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation and Principles of Consolidation

The accompanying condensed consolidated financial statements of Alnylam Pharmaceuticals, Inc. are unaudited and have been prepared in accordance with accounting principles generally accepted in the United States of America, or GAAP, applicable to interim periods and, in the opinion of management, include all normal and recurring adjustments that are necessary to state fairly the results of operations for the reported periods. Our condensed consolidated financial statements have also been prepared on a basis substantially consistent with, and should be read in conjunction with, our audited consolidated financial statements for the year ended December 31, 2014, which were included in our Annual Report on Form 10-K that was filed with the Securities and Exchange Commission, or SEC, on February 13, 2015. The year-end condensed consolidated balance sheet data was derived from our audited financial statements, but does not include all disclosures required by GAAP. The results of our operations for any interim period are not necessarily indicative of the results of our operations for any other interim period or for a full fiscal year.

The accompanying condensed consolidated financial statements reflect the operations of Alnylam and our wholly-owned subsidiaries. All significant intercompany accounts and transactions have been eliminated.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Net Loss Per Common Share

We compute basic net loss per common share by dividing net loss by the weighted-average number of common shares outstanding. We compute diluted net loss per common share by dividing net loss by the weighted-average number of common shares and dilutive potential common share equivalents then outstanding. Potential common shares consist of shares issuable upon the exercise of stock options (using the treasury stock method) and unvested restricted stock awards. Because the inclusion of potential common shares would be anti-dilutive for all periods presented, diluted net loss per common share is the same as basic net loss per common share.

The following table sets forth for the periods presented the potential common shares (prior to consideration of the treasury stock method) excluded from the calculation of net loss per common share because their inclusion would be anti-dilutive, in thousands:

Public Offering

In January 2015, we sold an aggregate of 5,447,368 shares of our common stock through an underwritten public offering at a price to the public of $95.00 per share. As a result of the offering, which included the full exercise of the underwriters’ option to purchase additional shares, we received aggregate net proceeds of $496.4 million, after deducting underwriting discounts and commissions and other offering expenses of $21.1 million.

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Fair Value Measurements

The fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities. Fair values determined by Level 2 inputs utilize data points that are observable, such as quoted prices (adjusted), interest rates and yield curves. Fair values determined by Level 3 inputs utilize unobservable data points for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. The fair value hierarchy level is determined by the lowest level of significant input.

Investments in Marketable Securities and Cash Equivalents

We invest our excess cash balances in short-term and long-term marketable debt and equity securities. We classify our investments in marketable debt securities as either held-to-maturity or available-for-sale based on facts and circumstances present at the time we purchased the securities. We invest primarily in money market funds, U.S. government-sponsored enterprise securities, U.S. treasury securities, high-grade corporate notes and commercial paper. Corporate notes also include foreign bonds denominated in U.S. dollars. At each balance sheet date presented, we classified all of our investments in debt and equity securities as available-for-sale. We report available-for-sale investments at fair value at each balance sheet date and include any unrealized holding gains and losses (the adjustment to fair value) in accumulated other comprehensive income (loss), a component of stockholders’ equity. At September 30, 2015, the balance in our accumulated other comprehensive loss was composed solely of activity related to our available-for-sale marketable securities, including our investment in equity securities of Regulus Therapeutics Inc., or Regulus. Realized gains and losses are determined using the specific identification method and are included in other income. We did not recognize any realized gains or losses from sales of our available-for-sale securities during the nine months ended September 30, 2015, and as a result, did not reclassify any amount out of accumulated other comprehensive income (loss) for the same period. If any adjustment to fair value reflects a decline in the value of the investment, we consider all available evidence to evaluate the extent to which the decline is “other than temporary,” including our intention to sell and, if so, mark the investment to market through a charge to our condensed consolidated statements of comprehensive income (loss). We did not record any impairment charges related to our fixed income marketable securities during the current period. Our marketable securities are classified as cash equivalents if the original maturity, from the date of purchase, is 90 days or less, and as marketable securities if the original maturity, from the date of purchase, is in excess of 90 days. Our cash equivalents are composed of money market funds, commercial paper and corporate notes.

We account for our investment in Regulus as an available-for-sale marketable security. Intraperiod tax allocation rules require us to allocate our provision for income taxes between continuing operations and other categories of earnings, such as other comprehensive income. In periods in which we have a year-to-date pre-tax loss from continuing operations and pre-tax income in other categories of earnings, such as other comprehensive income, we must allocate the tax provision to the other categories of earnings. We then record a related tax benefit in continuing operations. Upon sales of our available-for-sale marketable securities, we apply the aggregate portfolio approach to recognize the related tax provision or benefit into income (loss) from continuing operations. As a result, the disproportionate tax effect remains in accumulated other comprehensive income (loss) as long as we maintain an investment portfolio.

Recent Accounting Pronouncements

In May 2014, the Financial Accounting Standards Board, or FASB, issued a new revenue recognition standard which amends revenue recognition principles and provides a single, comprehensive set of criteria for revenue recognition within and across all industries. The new standard provides a five step framework whereby revenue is recognized when promised goods or services are transferred to a customer at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard also requires enhanced disclosures pertaining to revenue recognition in both interim and annual periods. In August 2015, the FASB deferred the effective date of the new revenue standard from January 1, 2017 to January 1, 2018. Early adoption is permitted any time after the original effective date, which for us is January 1, 2017. The standard allows for adoption using a full retrospective method or a modified retrospective method. We are currently evaluating the timing, method of adoption and the expected impact that the standard could have on our condensed consolidated financial statements and related disclosures.

In April 2015, the FASB amended its guidance on internal use software to clarify the accounting by customers for fees paid in a cloud computing arrangement. Under this guidance, if a cloud computing arrangement includes a software license, the software license element of the arrangement should be accounted for consistent with the customer’s accounting for other software licenses. If a cloud computing arrangement does not include a software license, the arrangement should be accounted for as a service contract. The new guidance will be effective for us on January 1, 2016. The adoption of this guidance is not expected to have a material impact on our condensed consolidated financial statements and related disclosures.

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Product Alliances

Genzyme Collaboration

In January 2014, we entered into a global, strategic collaboration with Genzyme Corporation, a Sanofi company, or Genzyme, to discover, develop and commercialize RNAi therapeutics as Genetic Medicines to treat orphan diseases. The 2014 Genzyme collaboration superseded and replaced the previous collaboration between us and Genzyme entered into in October 2012 to develop and commercialize RNAi therapeutics targeting transthyretin, or TTR, for the treatment of TTR-mediated amyloidosis, or ATTR amyloidosis, including patisiran and revusiran, in Japan and the Asia-Pacific region.

2012 Genzyme Agreement

Under the 2012 Genzyme agreement, Genzyme paid us an upfront cash payment of $22.5 million. We were also entitled to receive certain milestone payments under the 2012 Genzyme agreement. In the fourth quarter of 2013, we earned a milestone of $7.0 million based upon the completion of a successful patisiran Phase 2 clinical trial and a milestone of $4.0 million based upon the initiation of the Phase 3 clinical trial for patisiran.

Under the 2012 Genzyme agreement, the parties agreed to collaborate in the development and commercialization of licensed products, with Genzyme assuming primary responsibility in the Genzyme territory, which included Japan and the Asia-Pacific region, and us retaining primary responsibility in the rest of the world.

We determined that the deliverables under the 2012 Genzyme agreement included the license, a joint steering committee and any additional TTR-specific RNAi therapeutic compounds that comprised the ALN-TTR program. We also determined that, pursuant to the accounting guidance governing revenue recognition on multiple element arrangements, the license and undelivered joint steering committee and any additional TTR-specific RNAi therapeutic compounds did not have standalone value due to the specialized nature of the services to be provided by us. In addition, while Genzyme had the ability to grant sublicenses, it could not sublicense all or substantially all of its rights under the 2012 Genzyme agreement. The uniqueness of our services and the limited sublicense right were indicators that standalone value was not present in the arrangement. Therefore the deliverables were not separable and, accordingly, the license and undelivered services were treated as a single unit of accounting. We were unable to reasonably estimate the period of performance under the 2012 Genzyme agreement, as we were unable to estimate the timeline of our deliverables related to the deliverable for any additional TTR-specific RNAi therapeutic compounds. Through December 31, 2013, we had deferred all revenue, or $33.5 million, under the 2012 Genzyme agreement.

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2014 Genzyme Collaboration

In January 2014, we entered into the 2014 Genzyme collaboration. As noted above, the 2014 Genzyme collaboration superseded and replaced the 2012 Genzyme agreement.

The 2014 Genzyme collaboration is structured as an exclusive relationship for the worldwide development and commercialization of RNAi therapeutics in the field of Genetic Medicines, which includes our current and future Genetic Medicine programs that reach Human Proof-of-Principle Study Completion (as defined in the Genzyme master agreement), or Human POP, by the end of 2019, subject to extension to the end of 2021 in various circumstances. We will retain product rights in North America and Western Europe, referred to as the Alnylam Territory, while Genzyme will obtain exclusive rights to develop and commercialize collaboration products in the rest of the world, referred to as the Genzyme Territory, together with certain broader co-development/co-promote or worldwide rights for certain products. Genzyme’s rights, described in detail below, are structured as an opt-in that is triggered upon achievement of Human POP. We maintain development control for all programs prior to Genzyme’s opt-in and maintain development and commercialization control after Genzyme’s opt-in for all programs in the Alnylam Territory.

Specifically, in addition to its regional rights for our current and future Genetic Medicine programs in the Genzyme Territory, Genzyme has the right to either (i) co-develop and co-promote ALN-AT3 for the treatment of hemophilia and other rare bleeding disorders in the Alnylam Territory, with us maintaining development and commercialization control, or (ii) obtain a global license to ALN-AS1 for the treatment of hepatic porphyrias. Genzyme may exercise this selection right upon the completion of Human POP for both the ALN-AT3 and ALN-AS1 programs. Finally, Genzyme has the right for a global license to a single, future Genetic Medicine program that was not one of our defined Genetic Medicine programs as of the effective date of the 2014 Genzyme collaboration. We will retain global rights to any RNAi therapeutic Genetic Medicine program that does not reach Human POP by the end of 2019, subject to certain limited exceptions. We retain full rights to all current and future RNAi therapeutic programs outside of the field of Genetic Medicines, including the right to form new collaborations.

Under the 2014 Genzyme collaboration, Genzyme’s specific license rights and the programs for which Genzyme has opted-into include the following:

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Due to the uncertainty of pharmaceutical development and the high historical failure rates generally associated with drug development, we may not receive any additional milestone payments or any royalty payments from Genzyme under the 2014 Genzyme collaboration.

Under the master agreement, the parties will collaborate in the development of option products, with us leading development for all programs prior to Genzyme’s opt-in and also leading development and commercialization for all programs in the Alnylam Territory after Genzyme’s opt-in. If Genzyme does not exercise its option to license rights to a particular program, we will retain the exclusive right to develop and commercialize such program throughout the world, including the right to sublicense to third parties.

The 2014 Genzyme collaboration is governed by an alliance joint steering committee that is comprised of an equal number of representatives from each party. There are additional committees to manage various aspects of each regional, co-developed/co-promoted and global program. We and Genzyme intend to enter into supply agreements to provide for supply of collaboration products to Genzyme for clinical studies, and, at Genzyme’s request, commercial sales. Genzyme also has certain rights to manufacture collaboration products. Additionally, Genzyme has certain limited opt-out rights, as specified in the master agreement, upon which products revert fully back to us with no further obligations to Genzyme.

Upon the closing of the equity transaction in February 2014, we sold to Genzyme 8,766,338 shares of our common stock and Genzyme paid $700.0 million in aggregate cash consideration to us. As a condition to the closing of the equity transaction, Genzyme entered into an investor agreement with us. Under the investor agreement, until the earlier of the fifth anniversary of the expiration or earlier termination of the 2014 Genzyme collaboration and the date on which Genzyme and its affiliates cease to beneficially own at least 5% of our outstanding common stock, Genzyme and its affiliates are bound by certain “standstill” provisions. The standstill provisions include agreements not to acquire more than 30% of our outstanding common stock, call stockholder meetings, nominate directors other than those approved by our board of directors, subject to certain limited exceptions, or propose or support a proposal to acquire us. Further, Genzyme has agreed to vote, and cause its affiliates to vote, all shares of our voting securities they are entitled to vote, up to a maximum of 20% of our outstanding common stock, in a manner either as recommended by our board of directors or proportionally with the votes cast by our other stockholders, except with respect to certain change of control transactions or our liquidation or dissolution. Until Genzyme owns less than 7.5% of our outstanding common stock, subject to Genzyme’s limited right to maintain its ownership percentage as described below, if we issue common stock or securities convertible into or exercisable for common stock to a third party that holds at least 30% of our outstanding common stock or, in connection with a collaboration or license transaction, to a third party that will initially hold at least the percentage of our outstanding common stock represented by the shares purchased by Genzyme at the closing of the equity transaction, we will offer Genzyme an opportunity to amend the standstill and voting provisions in the investor agreement to be consistent with the terms provided to such third party.

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Under the investor agreement, Genzyme has also agreed not to dispose of any shares of common stock beneficially owned by it immediately after the closing of the stock purchase until the earlier of (i) December 31, 2019 (subject to extension by up to two years if Genzyme’s option to select additional compounds under the master agreement is extended beyond December 31, 2019) and (ii) six months after the expiration or earlier valid termination of the collaboration, in each case subject to earlier termination in the event certain clinical activities under the collaboration fail to occur. Following the expiration of this lock-up period, Genzyme will be permitted to sell such shares of common stock subject to certain limitations, including volume and manner of sale restrictions. Notwithstanding the foregoing, following the two-year anniversary of the closing of the stock purchase, in the event that the market price per share of our common stock is at least 100% higher than the market price per share of our common stock at closing of the stock purchase (in each case based upon a ten-day trailing average), Genzyme may sell up to 25% of its initial shares, subject to certain restrictions on post-lock-up period dispositions as described above.

Under the investor agreement, following the lock-up period, Genzyme will have three demand rights to require us to conduct a registered underwritten public offering with respect to the shares of common stock beneficially owned by Genzyme immediately after the closing of the stock purchase, subject to certain conditions. In addition, following the lock-up period, subject to certain conditions, Genzyme will be entitled to participate in registered underwritten public offerings by us if other selling stockholders are included in the registration.

The investor agreement provides that, until Genzyme owns less than 7.5% of our outstanding common stock, subject to Genzyme’s limited right to maintain its ownership percentage as described herein, in connection with new issuances of common stock, subject to certain exceptions, Genzyme will be entitled to a right of first offer to participate proportionally to maintain its then-current ownership percentage of our common stock. If Genzyme is not entitled to a right of first offer with respect to a new issuance, Genzyme will have the opportunity, on a post-transaction basis, to purchase additional shares sufficient to maintain its pre-transaction ownership percentage of our common stock (subject to the same 7.5% ownership threshold).

Finally, in the event Genzyme and its affiliates acquire at least 20% or more of our outstanding common stock, Genzyme will be entitled to appoint one individual to our board of directors. Genzyme will also be entitled to certain information rights, including with respect to financial information in the event Genzyme or its affiliates require such information for its own financial reporting purposes. The rights and restrictions under the investor agreement are subject to termination upon the occurrence of certain events.

We recorded the issuance of 8,766,338 shares of our common stock under the stock purchase agreement using the price of our common stock on the date the shares were issued to Genzyme. Based on the common stock price of $85.72, the fair value of the shares issued was $751.5 million, which was $51.5 million in excess of the proceeds received from Genzyme for the issuance of our common stock. This $51.5 million is being amortized on a straight-line basis over the performance period, which is currently approximately six years as described below. In addition, due to intraperiod tax allocation rules, upon closing of the equity transaction we recorded a benefit from income taxes of $15.2 million due to the Genzyme equity purchase being recorded in additional paid-in capital, net of tax.

In accordance with the investor agreement, as a result of our issuance of shares in connection with our acquisition of Sirna Therapeutics, Inc., or Sirna, in March 2014, Genzyme exercised its right to purchase an additional 344,448 shares of our common stock for $23.0 million. In addition, in January 2015, in connection with our public offering, Genzyme exercised its right to purchase directly from us, in concurrent private placements, 744,566 shares of common stock at the public offering price resulting in $70.7 million in proceeds to us. The sales of common stock to Genzyme were not registered as part of the public offering, though they were consummated simultaneously with the public offering.

Under the terms of the investor agreement, Genzyme also has the right each January to purchase a number of shares of our common stock based on the number of shares we issued during the previous year for compensation-related purposes. Genzyme exercised this right to purchase directly from us 196,251 shares of our common stock on January 22, 2015 for $18.3 million. The sale of these shares to Genzyme was consummated as a private placement.

In each instance, the purchase by Genzyme described above allowed Genzyme to maintain its ownership level of our common stock of approximately 12%.

We determined that the deliverables for the programs Genzyme is currently collaborating with us on include the licenses to our patisiran and revusiran clinical programs, which licenses were delivered to Genzyme upon the closing date of the transaction, and the associated development activities, joint steering committee participation and information exchange for these clinical programs. We also determined that, pursuant to the accounting guidance governing revenue recognition on multiple element arrangements, the

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license and associated undelivered development activities, joint steering committee participation and information exchange activities did not have standalone value due to the specialized nature of the services to be provided by us. In addition, while Genzyme has the ability to grant sublicenses, it cannot sublicense all or substantially all of its rights under the 2014 Genzyme collaboration. The uniqueness of our services and the limited sublicense rights are indicators that standalone value is not present in the arrangement. Therefore the deliverables are not separable and, accordingly, the license and undelivered services were treated as a single unit of accounting. When multiple deliverables are accounted for as a single unit of accounting, we base our revenue recognition model on the final deliverable. Under the 2014 Genzyme collaboration, the last deliverables for patisiran and revusiran are expected to be completed within approximately six years.

We determined that the total cash received from Genzyme under the now superseded 2012 Genzyme agreement reflects consideration for certain of the performance obligations for ALN-TTR programs included in the 2014 Genzyme collaboration. Therefore we are recognizing the $33.5 million of deferred revenue under the 2012 Genzyme agreement on a straight-line basis over the period of performance of the ALN-TTR programs, which, as noted above, is currently approximately six years. In addition, during the fourth quarter of 2014, we recognized as revenue a portion of the $25.0 million milestone payment earned in December 2014 equal to the percentage of the performance period completed when the milestone was earned. During the three and nine months ended September 30, 2015, we also recognized as revenue a portion of the expense reimbursement of $8.0 million and $26.1 million, respectively, due to us under the terms of the 2014 Genzyme collaboration equal to the percentage of the performance period completed to date. As future consideration is achieved, including any milestones or reimbursement for development activities, we will recognize as revenue a portion of these payments equal to the percentage of the performance period completed when the milestone or activities have been satisfied, multiplied by the amount of the payment. We will recognize the remaining portion of consideration received over the remaining performance period on a straight-line basis. At September 30, 2015, deferred revenue under the 2014 Genzyme collaboration was $25.3 million.

We determined that the opt-in rights that Genzyme has for future Genetic Medicine programs represent separate and additional deliverables that Genzyme may receive from us in future periods. Upon each opt-in by Genzyme, we have determined that each program and the related activities will represent a single unit of accounting and, consistent with our accounting policies, we will base our revenue recognition period on the final deliverable associated with each future opt-in, including ALN-AT3 where we expect to earn revenue, including cost reimbursement and potential milestones, beginning in 2016.

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During the nine months ended September 30, 2015, there were no transfers between Level 1 and Level 2 financial assets. The carrying amounts reflected in our condensed consolidated balance sheets for cash, billed and unbilled collaboration receivables, other current assets, accounts payable and accrued expenses approximate fair value due to their short-term maturities.

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The following tables summarize the fair value, accumulated other comprehensive income (loss) and intraperiod tax allocation regarding our investment in Regulus available-for-sale marketable securities at September 30, 2015 and 2014, and the activity for the nine months ended September 30, 2015 and 2014, in thousands:

We obtain fair value measurement data for our marketable securities from independent pricing services. We perform validation procedures to ensure the reasonableness of this data. This includes meeting with the independent pricing services to understand the methods and data sources used. Additionally, we perform our own review of prices received from the independent pricing services by comparing these prices to other sources and confirming those securities are trading in active markets.

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The following tables summarize our marketable securities, other than our holdings in Regulus noted above, at September 30, 2015 and December 31, 2014, in thousands:

5. COMMITMENTS AND CONTINGENCIES

Facility Leases

675 West Kendall Street

In April 2015, we entered into a non-cancelable real property lease, or the BMR lease, with BMR-675 West Kendall Street, LLC, or BMR, for laboratory and office space located at 675 West Kendall Street, Cambridge, Massachusetts. We intend to move our corporate headquarters to this location in early 2019.

Under the terms of the BMR lease, we will lease approximately 295,000 square feet of laboratory and office space. The term of the BMR lease will commence on May 1, 2018 and rent payments will become due commencing upon substantial completion of the building improvements, which is currently expected to be on or around February 1, 2019, and will continue for 15 years from the rent commencement date, with options to renew for two terms of five years each, subject to the terms of the BMR lease.

Annual rent under the BMR lease, exclusive of operating expenses and real property taxes, will be $19.8 million for the first year, with annual increases of 3% thereafter. Under the terms of the BMR lease, BMR will contribute a total of $56.1 million toward the cost of base building and tenant improvements.

The BMR lease contains customary provisions allowing BMR to terminate if we fail to remedy a breach of any of our obligations within specified time periods, or upon our bankruptcy or insolvency.

Under the terms of the BMR lease, for so long as we lease and occupy 70% or more of the rentable area of the leased premises and there are at least ten years remaining on the term of the BMR lease, we have a one-time right of first offer as to all of the rentable space in the building at 500 Kendall Street, Cambridge, Massachusetts, that is available for lease after the lease for such space that is currently in effect expires or terminates.

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101 Main Street

In May 2015, we entered into a non-cancelable real property lease agreement with RREEF America REIT II CORP. PPP, or RREEF, for office space located on several floors at 101 Main Street, Cambridge, Massachusetts. This lease supplements a lease entered into in March 2015 between us and RREEF for office space on the 10 ^th floor of the 101 Main Street location.

Under the terms of the 101 Main Street leases, we will lease approximately 72,000 square feet of office space at the 101 Main Street location. The term of the 10 ^th floor lease commenced in March 2015 and continues for four-years, with an option to renew for one five-year term, subject to the terms of the 10 ^th floor lease. The term of the additional lease at 101 Main Street will commence on January 1, 2016 and will continue for five and a half years, with an option to renew for one five-year term, subject to the terms of the additional lease.

Initial annual rent for the 10 ^th floor lease and the additional lease, exclusive of operating expenses and real property taxes, will be $1.7 million and $3.5 million, respectively, with annual increases of $1/square foot under each lease thereafter. Rent payments commenced in May 2015 under the 10 ^th floor lease and we expect rent payments to commence in May 2016 under the additional lease.

The 101 Main Street leases contain customary provisions allowing RREEF to terminate the leases if we fail to remedy a breach of any of our obligations within specified time periods, or upon our bankruptcy or insolvency.

As a result of the BMR lease and 101 Main Street leases, we expect our facility lease obligations through 2034 will increase by $409.3 million from the amount previously disclosed in our Annual Report on Form 10-K for the year ended December 31, 2014.

Future minimum payments under our non-cancelable leases as of December 31, 2014, as updated for the BMR lease and 101 Main Street leases entered into during the first half of 2015, are approximately as follows, in thousands:

Litigation

University of Utah Litigation

On March 22, 2011, The University of Utah, or Utah, filed a civil complaint in the United States District Court for the District of Massachusetts, or the MA District Court, against us, Max Planck Gesellschaft Zur Foerderung Der Wissenschaften e.V. and Max Planck Innovation GmbH, together, Max Planck, the Whitehead Institute for Biomedical Research, or Whitehead, the Massachusetts Institute of Technology, or MIT, and the University of Massachusetts, or UMass, claiming a professor at Utah is the sole inventor or, in the alternative, a joint inventor, of the Tuschl patents. Utah was seeking changes to the inventorship of the Tuschl patents, unspecified damages and other relief. On October 31, 2011, we, Max Planck, Whitehead, MIT and UMass filed a motion to dismiss. Also on October 31, 2011, UMass filed a motion to dismiss on separate grounds, which we, Max Planck, Whitehead and MIT joined. On December 31, 2011, Utah filed a second amended complaint dropping UMass as a defendant and adding as defendants several UMass officials. In June 2012, the MA District Court denied both motions to dismiss. We, Max Planck, Whitehead, MIT and UMass filed an appeal of the MA District Court’s ruling on the motion to dismiss for lack of jurisdiction and a motion requesting that the MA District Court stay the case pending the outcome of the appeal. In July 2012, the MA District Court stayed discovery in the case pending the outcome of the defendants’ appeal. In August 2013, the United States Court of Appeals for the Federal Circuit, or CAFC, affirmed the lower court’s ruling, in a split decision. In September 2013, we filed a petition with the CAFC for rehearing or

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rehearing en banc. In November 2013, the CAFC denied our petition for rehearing or rehearing en banc and remanded the case back to the MA District Court. In February 2014, we filed a petition for writ of certiorari from the Supreme Court and a motion to stay the lower court proceedings pending a decision from the Supreme Court on our petition. The MA District Court granted our motion to stay the proceedings, however, in June 2014 the Supreme Court denied our petition for certiorari and remanded the case back to the MA District Court for trial, which was scheduled to begin in November 2015. On March 30, 2015, Utah voluntarily dismissed its sole inventorship claims leaving joint inventorship and state law damages claims pending. Utah subsequently clarified that such dismissal was with prejudice. On March 31, 2015, we filed motions for summary judgment seeking dismissal of all remaining claims. An oral hearing on these motions was held on July 13, 2015. On September 28, 2015, the MA District Court granted both of our motions for summary judgment, finding that there was no collaboration between Dr. Bass and Dr. Tuschl, which is a pre-requisite for co-inventorship, and dismissing Utah’s state law damages claims as well. On October 28, 2015, Utah filed a notice of appeal. We remain firm in our belief that the inventorship of the Tuschl II patents as stated in the issued patents is correct.

On October 14, 2015, we filed a motion with the MA District Court seeking reimbursement of costs and fees associated with defending this action in the amount of approximately $8.0 million. While we believe a fee award is merited in this case, such awards are made at the discretion of the court. While we anticipate a ruling on this motion in mid-2016, the timing will be determined by the court.

Although the MA District Court has granted our motions for summary judgment and we remain firm in our belief that the inventorship of the Tuschl II patents as stated in the issued patents is correct, litigation is subject to inherent uncertainty and if Utah proceeds with an appeal, pursuant to its notice, and prevails, a court could ultimately rule against us. We have not recorded an estimate of the possible loss associated with this legal proceeding due to the uncertainties related to both the likelihood and the amount of any possible loss or range of loss.

Dicerna Litigation

On June 10, 2015, we filed a trade secret misappropriation lawsuit against Dicerna Pharmaceuticals, Inc., or Dicerna, in the Superior Court of Middlesex County, Massachusetts, seeking to stop misappropriation by Dicerna of our confidential, proprietary and trade secret information related to the RNAi assets we purchased from Merck Sharp & Dohme Corp., including certain GalNAc conjugate technology. In addition to permanent injunctive relief, we are also seeking monetary damages from Dicerna. On July 10, 2015, Dicerna filed its answer to our complaint, in which it denied our claims, along with initial discovery requests, to which we responded in a timely fashion. On July 27, 2015, Dicerna filed a motion seeking removal of the case to the Business Litigation Session of the Superior Court of Suffolk County, which we opposed. On August 31, 2015, the Court denied Dicerna’s motion.

Although we believe we have meritorious claims in this matter, litigation is subject to inherent uncertainty and a court could ultimately rule against us. In addition, litigation and related matters are costly and may divert the attention of our management and other resources that would otherwise be engaged in other activities.

Our accounting policy for accrual of legal costs is to recognize such expenses as incurred.

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