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QUESTIONS AND ANSWERS

        The following provides answers to some questions that you, as either a stockholder of Midstates or a stockholder of Amplify, may have regarding the merger. However, this section provides only summary information. Accordingly, Midstates and Amplify urge you to carefully read the remainder of this joint proxy statement/prospectus, the merger agreement and all other annexes, and any documents incorporated by reference.

Q:

Why am I receiving this document?

A:

Amplify, Midstates and Merger Sub have entered into an Agreement and Plan of Merger, dated as of May 5, 2019 (as may be amended from time to time, the "Merger Agreement"), providing for the merger of Merger Sub with and into Amplify, with Amplify surviving the merger as a direct wholly owned subsidiary of Midstates. The merger agreement is described in more detail in this joint proxy statement/prospectus under the caption "The Merger Agreement," starting at page 162.

In order for Midstates and Amplify to complete the merger, Midstates stockholders must approve the proposal to issue shares of Midstates common stock (such issuance, the "stock issuance") to Amplify stockholders pursuant to the merger agreement (the "stock issuance proposal") and Amplify stockholders must approve the proposal to adopt the merger agreement (the "merger agreement proposal"), along with all other conditions to the merger either being satisfied or waived.

This joint proxy statement/prospectus serves as the proxy statement through which Midstates and Amplify will solicit proxies to obtain the necessary stockholder approvals for the merger. It also serves as the prospectus by which Midstates will issue shares of its common stock as consideration in the merger.

This joint proxy statement/prospectus, which you should carefully read in its entirety, contains important information about the merger, the stock issuance and other matters.

Q:

What am I being asked to vote on?

A:

Midstates :    If you are a holder of Midstates common stock, you are being asked to approve (i) the stock issuance proposal described above, (ii) the election of eight directors (the "election of directors proposal") to serve until the next annual meeting of Midstates or until the merger is complete, whereupon the Midstates board will be reconstituted as described in this joint proxy statement/prospectus, (iii) on a non-binding advisory basis, the compensation of Midstates' named executive officers (the "executive compensation proposal"), (iv) the ratification of appointment of Grant Thornton LLP as Midstates' independent registered public accountants for 2019 and (v) the adjournment of the Midstates annual meeting, if necessary or appropriate, to solicit additional proxies, if there are not sufficient votes cast at the Midstates annual meeting, to approve the stock issuance proposal (the "Midstates adjournment proposal").

Amplify :    If you are a holder of Amplify common stock, you are being asked to approve (i) the merger agreement proposal, (ii) on an advisory (non-binding) basis, the compensation that may be paid or become payable to Amplify's named executive officers in connection with the merger (the "advisory compensation proposal") and (iii) the adjournment of the Amplify special meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes cast at the Amplify special meeting to approve the merger agreement proposal (the "Amplify adjournment proposal"). Pursuant to the voting agreements, certain stockholders of Amplify have committed to vote their shares of Amplify common stock representing approximately 58.3% of the total voting power of the issued and outstanding shares of Amplify common stock as of May 31, 2019 in favor of the merger agreement proposal and the Amplify adjournment proposal. Accordingly, as long as

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there is not an Amplify recommendation change with respect to the merger agreement proposal, approval of the merger agreement proposal at the Amplify special meeting is assured.

Your vote is very important and Midstates and Amplify encourage you to submit your proxy as soon as possible.

Q:

What will happen in the merger?

A:

The Merger Agreement sets forth the terms and conditions of the proposed business combination of Midstates and Amplify. Under the Merger Agreement, Merger Sub will merge with and into Amplify, with Amplify surviving the merger as a wholly owned subsidiary of Midstates.

A complete copy of the Merger Agreement is attached to this joint proxy statement/prospectus as Annex A. For a more complete discussion of the proposed Merger, its effects and the other transactions contemplated by the Merger Agreement, see "The Merger" beginning on page 93 of this joint proxy statement/prospectus.

Q:

What is Midstates' strategic rationale for the merger?

A:

Midstates has transitioned from a growth-orientated exploration and production company to adopting a business plan emphasizing free cash flow generation, and the Midstates board considers the merger with Amplify to be an effective method of exploiting synergies and cost efficiencies to improve returns. The Midstates board estimates that the transaction will result in an immediate increase in value through annual synergies totaling at least $20 million and will allow the combined company the opportunity to move farther down the cost curve by spreading fixed costs over more production. The Midstates board members determined that the operational footprint, strong cost structure and balance sheet of the combined company would enable it to advance its business plan. Further, the Midstates board believes that its current business plan will face fewer challenges following the combination with Amplify due to the increased like-kind cash flow generating assets in the combined company, which the Midstates board believes will help create a more stable production and expense profile. The combined portfolios of the two companies will also provide access to a larger set of reinvestment opportunities and more optionality, including multiple opportunities for the optimization of non-strategic assets, if desired, as well as future opportunistic combinations and acquisitions that create value through synergies and free cash flow accretion. In addition, the combined entity is expected to have the necessary liquidity and low leverage profile to provide flexibility during volatile commodity price cycles. The Midstates board also believes that the larger size of the combined company could increase analyst and investor interest, which in turn could lead to an improvement in market value.

Q:

What is Amplify's strategic rationale for the merger?

A:

The Amplify board considered consolidation to be an effective method of exploiting synergies and cost efficiencies to improve returns. The combined company is expected to compare favorably to other similarly sized resource companies on a general and administrative expense per unit of production basis. In addition, the combined entity would have a superior capital structure, with the necessary liquidity and leverage profile to provide flexibility during volatile commodity price cycles. The Amplify board members determined that the operational footprint, strong cost structure and balance sheet of the combined company will enable the combined company to advance the combined company's assets for less capital and realize the projected cost synergies. The size of the combined company is expected to lead to an improved leverage profile, a significantly lower cost of capital and enhanced free cash flow generation. Amplify's stockholders will have a continuing influence in the execution of the strategy and business plan of the combined company through the appointment of four Amplify directors (in addition to Messrs. Proman and Lederman) to the

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combined company board, which will be increased to eight directors in connection with the consummation of the merger. The combined company is expected to assume Midstates' listing on the NYSE upon consummation of the merger and to trade under the Amplify ticker "AMPY." Amplify expects that trading liquidity will be significantly improved for Amplify stockholders, especially as financial equity research coverage increases over time. For additional information regarding the strategic rationale of the merger see "The Merger—Recommendation of the Amplify Board and Reasons for the Merger" and "Summary—Recommendation of the Amplify Board and Reasons for the Merger."

Q:

When and where is the Midstates annual meeting?

A:

The Midstates annual meeting will be held on                    , 2019 at the offices of Latham & Watkins, LLP ("Latham"), located at 811 Main St., Suite 3700, Houston Texas, 77002, at                local time.

Q:

When and where is the Amplify special meeting?

A:

The Amplify special meeting will be held on                    , 2019 at                    , at                local time.

Q:

What will Amplify stockholders receive for their shares of Amplify common stock in the merger?

A:

At the effective time of the merger (the "effective time," and the date of the effective time, the "closing date of the merger"), each share of Amplify common stock issued and outstanding immediately prior to the effective time (with certain exceptions described in this joint proxy statement/prospectus) will be cancelled and converted automatically into the right to receive 0.933 shares of Midstates common stock (the "exchange ratio") in certificated or book-entry form (such shares of Midstates common stock issuable under the merger agreement, the "merger consideration").

In addition, Amplify will take all actions as may be necessary so that, at the effective time, each outstanding stock option and performance- and service-based restricted stock unit award will be treated as described in "The Merger—Treatment of Amplify Equity Awards in the Merger."

Furthermore, pursuant to the terms of the merger agreement, Midstates and Amplify will ensure that the holders of the warrants (the "Amplify warrants") outstanding under Amplify's Warrant Agreement dated as of May 4, 2017 (the "Amplify warrant agreement") by and between Amplify and American Stock Transfer & Trust Company, LLC ("AST") have the right to acquire 0.933 shares of Midstates common stock per Amplify warrant upon exercise at an exercise price of $42.60 per share. Midstates and Amplify may also enter into a written agreement providing for Midstates' assumption of Amplify's obligations under the Amplify warrant agreement. See "The Merger—Interests of Certain Amplify Directors and Executive Officers in the Merger—Treatment of Amplify Warrants."

For additional information regarding the consideration to be received in the merger, see "The Merger—Effects of the Merger."

Q:

If I am an Amplify stockholder, how will I receive the merger consideration to which I am entitled?

A:

As soon as reasonably practicable after the effective time, an exchange agent will mail a letter of transmittal and instructions for use in effecting the surrender of certificates of Amplify common stock ("Amplify stock certificates") and book-entry shares representing shares of Amplify common stock ("Amplify book-entry shares") in exchange for the merger consideration to each holder of

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record of Amplify common stock (whose shares were cancelled and converted into the right to receive the merger consideration pursuant to the merger agreement). Upon receipt by the exchange agent of (i) either Amplify stock certificates or Amplify book-entry shares and (ii) a signed letter of transmittal and such other documents as may be required pursuant to such instructions, the holder of such shares will be entitled to receive the merger consideration in exchange therefor.

Q:

What will holders of Amplify equity awards receive in the merger?

A:

Pursuant to the merger agreement, the following will occur at the effective time:

•

Amplify Stock Options :  All outstanding Amplify stock options will convert into Midstates stock options, subject to the same terms and conditions as were in effect prior to the effective time, at an exercise price adjusted after taking into effect the exchange ratio.

•

Amplify RSUs :  Pursuant to the terms of the outstanding Amplify restricted stock units ("Amplify RSUs") (other than Amplify PSUs (as defined below)), all outstanding Amplify RSUs will, pursuant to their terms, become fully vested and will be settled in shares of Amplify common stock. These shares of Amplify common stock will then convert into shares of Midstates common stock based on the exchange ratio. However, certain members of the Amplify board and Amplify senior management have waived this accelerated vesting. For those members of the Amplify board and Amplify management, the Amplify RSUs will convert into Midstates restricted stock units ("Midstates RSUs") based on the exchange ratio, and remain subject to the vesting terms set forth in the applicable award agreement immediately prior to conversion. Amplify intends to seek additional waivers from all holders of Amplify RSUs before the closing of the merger.

•

Amplify PSUs :  All outstanding RSUs that are subject to both performance- and service-based vesting conditions ("Amplify PSUs") will convert into shares of Midstates common stock based on the exchange ratio, with performance-vesting conditions determined based on Amplify's closing stock price on the last trading day prior to the closing date of the merger. However, certain members of the Amplify board and Amplify senior management have waived this accelerated vesting. For those members of the Amplify board and Amplify management, the Amplify PSUs will convert into Midstates RSUs subject to performance- and service-based vesting conditions ("Midstates PSUs") based on the exchange ratio, and remain subject to the vesting terms set forth in the applicable award agreement immediately prior to conversion. Amplify intends to seek additional waivers from all holders of Amplify PSUs before the closing of the merger.

Furthermore, pursuant to the terms of the merger agreement, Midstates and Amplify will ensure that the holders of the Amplify warrants have the right to acquire 0.933 shares of Midstates common stock per Amplify warrant upon the exercise of Amplify warrants at an exercise price of $42.60 per share. Midstates and Amplify may also enter into a written agreement providing for Midstates' assumption of Amplify's obligations under the Amplify warrant agreement. See "The Merger—Interests of Certain Amplify Directors and Executive Officers in the Merger—Treatment of Amplify Warrants."

For additional information regarding the treatment of Amplify equity awards, see "The Merger—Treatment of Amplify Equity Awards in the Merger."

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Q:

Who will own Midstates immediately following the merger?

A:

Midstates and Amplify estimate that, upon completion of the merger, current Midstates stockholders, collectively, and current Amplify stockholders, collectively, will each own approximately 50% of the outstanding common stock of the combined company.

Q:

Why are Amplify stockholders being asked to cast an advisory (non-binding) vote to approve the advisory compensation proposal?

A:

Section 14A of the Exchange Act, which was enacted as part of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010, requires Amplify to provide its stockholders with the opportunity to vote to approve, on an advisory (non-binding) basis, the compensation that may be paid or become payable to Amplify's named executive officers in connection with the merger, as disclosed in this joint proxy statement/prospectus, including the compensation table and the related narrative for named executive officer compensation disclosures set forth in "The Merger—Interests of Certain Amplify Directors and Executive Officers in the Merger."

Q:

What will happen if Amplify's stockholders do not approve the advisory (non-binding) vote at the Amplify special meeting?

A:

Amplify stockholder approval of the advisory compensation proposal is not a condition to completion of the merger. The advisory compensation proposal is merely an advisory vote that will not be binding on Amplify, Midstates or their respective boards of directors. Further, the underlying plans and arrangements are contractual in nature and not, by their terms, subject to stockholder approval. Accordingly, regardless of the outcome of the advisory vote, if the merger is consummated, the eligibility of the Amplify named executive officers for such payments and benefits will not be affected by the outcome of the advisory vote.

Q:

How important is my vote?

A:

Your vote " FOR " each proposal presented at the Midstates annual meeting or the Amplify special meeting, as applicable, is very important, and you are encouraged to submit a proxy as soon as possible. The merger between Midstates and Amplify cannot be completed without the approval of the stock issuance proposal by the Midstates stockholders and the approval of the merger agreement proposal by Amplify stockholders.

Midstates .    Approval of the stock issuance proposal requires the affirmative vote of a majority of votes cast by Midstates stockholders entitled to vote thereon and present in person or represented by proxy at the Midstates annual meeting. Abstentions are considered Midstates common stock present and entitled to vote and will have the same effect as a vote "against" the stock issuance proposal. The failure of any Midstates stockholder to submit a vote will not be counted in determining the votes cast in connection with this proposal and therefore will have no effect on the outcome of the stock issuance proposal. Approval of the election of the directors proposal requires the affirmative vote of the holders of a majority of the shares of Midstates common stock present in person or represented by proxy and entitled to vote thereon at the Midstates annual meeting. Abstentions are considered shares of Midstates common stock present and entitled to vote and will have the same effect as votes "against" the election of directors proposal. Approval of the executive compensation proposal requires the affirmative vote of the holders of a majority of the shares of Midstates common stock present in person or represented by proxy and entitled to vote thereon at the Midstates annual meeting. Abstentions are considered shares of Midstates common stock present and entitled to vote and will have the same effect as votes "against" the executive compensation proposal. Since the executive compensation proposal is not binding, if the merger is completed, the compensation that is the subject of the executive compensation proposal,

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which includes amounts Midstates or Amplify are contractually obligated to pay, would still be paid regardless of the outcome of the advisory (non-binding) vote. Approval of the auditor ratification proposal requires the affirmative vote of the holders of a majority of the shares of Midstates common stock present in person or represented by proxy and entitled to vote thereon at the Midstates annual meeting. Abstentions are considered Midstates common stock present and entitled to vote and will have the same effect as a vote "against" the auditor ratification proposal. Brokers will have discretionary authority to vote in the absence of timely instructions from their customers. Approval of the Midstates adjournment proposal requires the affirmative vote of the holders of a majority of the shares of Midstates common stock present in person or represented by proxy and entitled to vote thereon at the Midstates annual meeting. Abstentions are considered shares of Midstates common stock present and entitled to vote and will have the same effect as votes "against" the Midstates adjournment proposal.

Certain of Midstates stockholders who in the aggregate own approximately 35.5% of the outstanding shares of Midstates common stock are parties to separate voting and support agreements (the "Amplify voting agreements") with Amplify, whereby such stockholders have agreed, subject to the terms and conditions of the Amplify voting agreements, to vote their shares in favor of the stock issuance proposal at the Midstates annual meeting. For more information about the Amplify voting agreements, see "The Merger—Voting and Support Agreements."

Amplify .    Approval of the merger agreement proposal requires the affirmative vote of the holders of a majority of the issued and outstanding shares of Amplify common stock entitled to vote thereon. The failure of any Amplify stockholder to submit a vote, or any abstention, will have the same effect as voting against the merger agreement proposal. Approval of the advisory compensation proposal requires the affirmative vote of a majority of votes cast by holders of the issued and outstanding shares of Amplify common stock entitled to vote thereon and present in person or represented by proxy at the Amplify special meeting. Abstentions are considered shares of Amplify common stock present and entitled to vote and will have the same effect as votes "against" the advisory compensation proposal. Since the advisory compensation proposal is not binding, if the merger agreement is adopted by Amplify stockholders and the merger is completed, the compensation that is the subject of the advisory compensation proposal, which includes amounts Midstates or Amplify are contractually obligated to pay, would still be paid regardless of the outcome of the advisory (non-binding) vote. The Amplify adjournment proposal requires the affirmative vote of a majority of votes cast by holders of the issued and outstanding shares of Amplify common stock entitled to vote thereon and present in person or represented by proxy at the Amplify special meeting. Abstentions are considered shares of Amplify common stock present and entitled to vote and will have the same effect as votes "against" the Amplify adjournment proposal.

Certain of Amplify's stockholders who in the aggregate own approximately 58.3% of the outstanding shares of Amplify common stock are parties to the Midstates voting agreements (together with the Amplify voting agreements, the "voting agreements") with Midstates, whereby such stockholders have agreed, subject to the terms and conditions of the voting agreements, to vote their shares in favor of the adoption of the merger agreement proposal at the Amplify special meeting. For more information about the voting agreements, see "The Merger—Voting and Support Agreements."

Q:

How do the Midstates board and the Amplify board recommend that I vote?

A:

The Midstates board of directors (the "Midstates board") has (i) determined that the merger agreement and the transactions contemplated thereby, including the merger and the issuance of Midstates common stock, are in the best interests of, and advisable to, Midstates and its stockholders, (ii) approved and adopted the merger agreement and the transactions contemplated

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thereby, including the merger and the stock issuance, (iii) approved the execution, delivery and performance by Midstates of the merger agreement, including the merger and the stock issuance, upon the terms and subject to the conditions contained therein, (iv) directed that the stock issuance required under the terms of the merger agreement be submitted to the holders of Midstates common stock for approval at the Midstates annual meeting and (v) resolved to recommend that the holders of Midstates common stock approve the stock issuance. For a detailed description of the various factors considered by the Midstates board, see "The Merger—Recommendation of the Midstates Board and Reasons for the Merger."

Accordingly, the disinterested members of the Midstates board unanimously recommend that Midstates stockholders vote " FOR " the stock issuance proposal, " FOR " the election of directors proposal, " FOR " the executive compensation proposal, " FOR " the auditor ratification proposal and " FOR " the Midstates adjournment proposal.

The Amplify board of directors (the "Amplify board"), after considering the various factors described under "The Merger—Recommendation of the Amplify Board and Reasons for the Merger," the comprehensive process conducted by the Amplify board and the alternatives to the merger (including remaining as a stand-alone company), has (i) determined that the merger agreement and the transactions contemplated thereby, including the merger, are advisable, fair to, and in the best interests of Amplify and its stockholders, (ii) approved and declared advisable the merger agreement and the transactions contemplated thereby, including the merger, (iii) approved the execution and delivery by Amplify of the merger agreement, the performance by Amplify of its covenants and agreements contained therein and the consummation of the transactions contemplated thereby, including the merger, upon the terms and subject to the conditions contained therein, (iv) directed that the merger agreement be submitted to the holders of Amplify common stock at a stockholders' meeting to approve its adoption and (v) resolved to recommend that the holders of Amplify common stock approve the adoption of the merger agreement.

Accordingly, the disinterested members of the Amplify board unanimously recommend that you vote " FOR " the merger agreement proposal, " FOR " the advisory compensation proposal and " FOR " the Amplify adjournment proposal.

Q:

Will the Midstates common stock received at the time of completion of the merger be traded on an exchange?

A:

Yes. It is a condition to the consummation of the merger that the shares of Midstates common stock to be issued to Amplify stockholders in connection with the merger be approved for listing on the New York Stock Exchange (the "NYSE"), subject to official notice of issuance. Shares of Midstates common stock are currently listed on the NYSE under the symbol "MPO." When the merger is completed, shares of the combined company's common stock will be listed on the NYSE under the symbol "AMPY." Shares of Amplify common stock are currently quoted on the OTCQX U.S. Premier marketplace (the "OTC") under the symbol "AMPY." In connection with the merger, Amplify common stock will be cancelled and will cease to be quoted on the OTC.

Q:

How will Midstates stockholders be affected by the merger?

A:

Upon completion of the merger, each Midstates stockholder will hold the same number of shares of Midstates common stock that such stockholder held immediately prior to completion of the merger. As a result of the merger, Midstates stockholders will own shares in a larger company with more assets. However, because in connection with the merger, Midstates will be issuing additional shares of Midstates common stock to Amplify stockholders in exchange for their shares of Amplify common stock, each outstanding share of Midstates common stock immediately prior to the merger will represent a smaller percentage of the aggregate number of shares of Midstates common stock outstanding after the merger.

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Q:

What are the material U.S. federal income tax consequences of the merger?

A:

The closing of the transactions contemplated by the merger agreement are conditioned upon the receipt by each of Midstates and Amplify of an opinion from counsel that, on the basis of facts, assumptions, representations and exclusions set forth or described in such opinion, the merger and the second merger, taken together, will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended, which is referred to as the Internal Revenue Code. Assuming the merger and the second merger, taken together, constitute a reorganization, subject to the limitations and qualifications described in the section entitled "The Merger—Material U.S. Federal Income Tax Consequences" beginning on page 153 of this joint proxy statement/prospectus, U.S. holders whose shares of Amplify common stock are exchanged in the merger for shares of Midstates common stock generally will not recognize any gain or loss for United States federal income tax purposes upon such exchange.

For the definition of a "U.S. holder" and a more detailed discussion of the material United States federal income tax consequences of the merger, please see the section entitled "The Merger—Material U.S. Federal Income Tax Consequences" beginning on page 153 of this joint proxy statement/prospectus.

The tax consequences of the merger to any particular stockholder will depend on that stockholder's particular facts and circumstances. Accordingly, you are urged to consult your tax advisor to determine your tax consequences from the merger.

Q:

When do Midstates and Amplify expect to complete the merger?

A:

Midstates and Amplify currently expect to complete the merger in the third quarter of 2019. However, neither Midstates nor Amplify can predict the actual date on which the merger will be completed, nor can the parties assure that the merger will be completed, because completion is subject to conditions beyond either company's control. See "Risk Factors—Risks Relating to the Merger," "The Merger—Regulatory Approvals" and "The Merger Agreement—Conditions to Closing."

Q:

What are the conditions to the completion of the merger?

A:

The obligations of Midstates and Amplify to consummate the merger are subject to the satisfaction or waiver (to the extent permissible under applicable laws) of the following mutual conditions:

•

adoption of the stock issuance proposal by Midstates stockholders;

•

adoption of the merger agreement proposal by Amplify stockholders;

•

effectiveness of the registration statement on Form S-4 filed by Midstates in connection with the stock issuance, of which this joint proxy statement/prospectus forms a part, having been declared by the SEC and absence of any stop order suspending the effectiveness of such Form S-4 having been issued by the SEC or any proceedings for that purpose having been initiated or threatened by the SEC;

•

absence of any order, decree, ruling, injunction or other action that is in effect (whether temporary, preliminary or permanent) restraining, enjoining or otherwise prohibiting the consummation of the merger, and no law having been adopted that makes consummation of the merger illegal or otherwise prohibited;

•

expiration or termination of any waiting period applicable to the merger under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended (the "HSR Act"); and

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•

approval of the listing of the additional shares of Midstates common stock to be issued to Amplify stockholders in connection with the merger on the NYSE, subject to official notice of issuance.


There are certain other additional customary conditions to the completion of the merger discussed further in "The Merger Agreement—Conditions to Closing."

Q:

What happens if the merger is not completed?

A:

If the stock issuance is not approved by Midstates stockholders, the merger agreement is not adopted by Amplify stockholders or the merger is not completed for any other reason, Amplify stockholders will not receive the merger consideration. Instead, each of Midstates and Amplify will remain an independent company. Amplify common stock will continue to be quoted on the OTC and Amplify will continue to file periodic reports with the SEC, and Midstates common stock will continue to be quoted on the NYSE and Midstates will continue to file periodic reports with the SEC.

Under specified circumstances, Midstates or Amplify may be required to reimburse the other party's expenses or pay a termination fee upon termination of the merger agreement, as described under "The Merger Agreement—Fees and Expense Reimbursement Relating to the Termination of the Merger Agreement."

Q:

Will all of the Midstates directors elected at the Midstates annual meeting continue to serve if the merger is completed?

A:

No. Upon the completion of the merger, the board of directors of the combined company will consist of the following eight members: David M. Dunn, Christopher W. Hamm, Scott L. Hoffman, Randal T. Klein, Evan S. Lederman, Kenneth Mariani (chief executive officer), David H. Proman (chairman) and Todd R. Snyder. Messrs. Dunn, Hamm, Hoffman and Mariani are current directors of Amplify. Messrs. Klein and Snyder are current directors of Midstates. Messrs. Proman and Lederman currently serve on both Midstates' board of directors and Amplify's board of directors.

Q:

How many votes may I cast?

A:

Midstates.     Each outstanding share of Midstates common stock entitles its holder of record to one vote on each matter to be considered at the Midstates annual meeting. Only Midstates stockholders who held shares of Midstates common stock at the close of business on                    , 2019 are entitled to vote at the Midstates annual meeting and any adjournment or postponement of the Midstates annual meeting, so long as such shares remain outstanding on the date of the Midstates annual meeting.

Amplify.     Each outstanding share of Amplify common stock entitles its holder of record to one vote on each matter to be considered at the Amplify special meeting. Only Amplify stockholders who held shares of Amplify common stock at the close of business on                    , 2019 are entitled to vote at the Amplify special meeting and any adjournment or postponement of the Amplify special meeting, so long as such shares remain outstanding on the date of the Amplify special meeting.

Q:

Who can vote at, and what are the record dates of, each of the Midstates annual meeting and the Amplify special meeting?

A:

Midstates.     All Midstates stockholders who hold shares of Midstates common stock of record at the close of business on                    , 2019, the record date for the Midstates annual meeting, are entitled to receive notice of and to vote at the Midstates annual meeting.

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Amplify.     All Amplify stockholders who hold shares of Amplify common stock of record at the close of business on                    , 2019 the record date for the Amplify special meeting, are entitled to receive notice of and to vote at the Amplify special meeting.

Q:

What constitutes a quorum at each of the Midstates annual meeting and the Amplify special meeting?

A:

In order for business to be conducted at each of the Midstates annual meeting and the Amplify special meeting, a quorum must be present. A quorum at the Midstates annual meeting and the Amplify special meeting each requires the presence, in person or represented by proxy, of holders of a majority of the shares of Midstates or Amplify common stock, respectively, entitled to vote at the Midstates annual meeting or the Amplify special meeting, respectively.

Q:

What do I need to do now?

A:

After you have carefully read and considered the information contained and incorporated by reference into this joint proxy statement/prospectus, please submit your proxy via the Internet or by telephone in accordance with the instructions set forth on the enclosed proxy card, or complete, sign, date and return the enclosed proxy card in the postage-prepaid envelope provided as soon as possible so that your shares will be represented and voted at the Midstates annual meeting or the Amplify special meeting, as applicable.

Additional information on voting procedures can be found under "Midstates Annual Meeting" and under "Amplify Special Meeting."

Q:

Should I send in my stock certificates or submit my book-entry shares now?

A:

No. As soon as reasonably practicable after the effective time (but no later than the third business day after the closing date of the merger), an exchange agent will mail to each holder of record of Amplify common stock (whose shares were converted into the right to receive the merger consideration pursuant to the merger agreement) a letter of transmittal and instructions for use in effecting the surrender of Amplify stock certificates and Amplify book-entry shares in exchange for the merger consideration. If you are a Midstates stockholder, you should retain your certificates or book-entry positions, as you will continue to hold the shares of Midstates common stock you currently own.

Q:

How will my proxy be voted?

A:

If you submit your proxy via the Internet, by telephone or by completing, signing, dating and returning the enclosed proxy card, your proxy will be voted in accordance with your instructions.

Additional information on voting procedures can be found under "Midstates Annual Meeting" and under "Amplify Special Meeting."

Q:

Who will count the votes?

A:

The votes at the Midstates annual meeting will be counted by an independent inspector of election appointed by the Midstates board. The votes at the Amplify special meeting will be counted by an independent inspector of election appointed by the Amplify board.

Q:

May I vote in person?

A:

Yes. If you are a stockholder of record of Midstates at the close of business on                    , 2019 or an Amplify stockholder of record on the close of business on                     , 2019, you may attend the Midstates annual meeting or Amplify special meeting, as applicable, and vote your shares in

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person, in lieu of submitting your proxy by Internet, telephone or by completing, signing, dating and returning the enclosed proxy card. Please note attendance at the Midstates annual meeting or the Amplify special meeting, as applicable, alone will not cause the voting of your shares; you must affirmatively vote the proxy card or meeting ballot provided.

If you are a beneficial owner of Midstates common stock or a beneficial owner of Amplify common stock, you are also invited to attend the Midstates annual meeting or the Amplify special meeting, as applicable. However, because you are not the Midstates stockholder of record or Amplify stockholder of record, as applicable, you may not vote your shares in person at the Midstates annual meeting or the Amplify special meeting, as applicable, unless you request and obtain a proxy issued in your own name from your bank, broker or nominee.

If you appoint a non-management proxyholder, please make sure they are aware and ensure they will attend the applicable company meeting with the proper authority from you, the Midstates stockholder or Amplify stockholder, as applicable, for your vote to count.

Q:

What must I bring to attend my company meeting?

A:

Only Midstates stockholders of record or Amplify stockholders of record, as applicable, as of the close of business on the applicable record date, beneficial owners of Midstates common stock or beneficial owners of Amplify common stock as of the close of business on the applicable record date, holders of valid proxies for the Midstates annual meeting or Amplify special meeting, as applicable and invited guests of Midstates or Amplify, as applicable, may attend the Midstates annual meeting or Amplify special meeting, as applicable. All attendees should be prepared to present government-issued photo identification (such as a driver's license or passport) for admittance. The additional items, if any, that attendees must bring depend on whether they are Midstates stockholders or Amplify stockholders of record, as applicable, beneficial owners of Midstates common stock or beneficial owners of Amplify common stock or proxy holders.

Additional information on attending the Midstates annual meeting and the Amplify special meeting can be found under "Midstates Annual Meeting" and under "Amplify Special Meeting."

Q:

What should I do if I receive more than one set of voting materials for either company meeting?

A:

You may receive more than one set of voting materials for the Midstates annual meeting, the Amplify special meeting or both, including multiple copies of this joint proxy statement/prospectus and multiple proxy cards or voting instruction forms. For example, if you hold your Midstates common stock or Amplify common stock in more than one brokerage account, you will receive a separate voting instruction form for each brokerage account in which you hold shares. If you are a holder of record and your shares are registered in more than one name, you will receive more than one proxy card. Please submit each separate proxy or voting instruction form that you receive by following the instructions set forth in each separate proxy or voting instruction form.

Q:

What's the difference between holding shares as a stockholder of record and holding shares as a beneficial owner?

A:

If your shares of Midstates common stock are registered directly in your name with Midstates' transfer agent, AST, or your shares of Amplify common stock are registered directly in your name with Amplify's transfer agent, AST, you are considered, with respect to those shares, to be the Midstates stockholder of record, in the case of Midstates, or the Amplify stockholder of record, in the case of Amplify. If you are such a stockholder of record, then this joint proxy statement and your proxy card have been sent directly to you by Midstates or Amplify, as applicable.

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If your Midstates common stock or Amplify common stock are held through a bank, broker or other nominee, you are considered the beneficial owner of the Midstates common stock or Amplify common stock held in "street name." In that case, this joint proxy statement/prospectus has been forwarded to you by your bank, broker or other nominee. As the beneficial owner, you have the right to direct your bank, broker or other nominee how to vote your shares by following their instructions for voting, and you are also invited to attend in person the Midstates annual meeting or the Amplify special meeting, as applicable. However, because you are not the Midstates stockholder or Amplify stockholder of record, you may not vote your shares of Midstates common stock in person at the Midstates annual meeting or your shares of Amplify common stock at the Amplify special meeting, as applicable, unless you request and obtain a proxy issued in your own name from your bank, broker or nominee.

If you appoint a non-management proxyholder, please make sure they are aware and ensure they will attend the applicable company meeting with the proper authority from you, the Midstates stockholder or Amplify stockholder, for your vote to count.

Q:

If my shares are held in "street name" by my broker, bank or other nominee, will my broker, bank or other nominee automatically vote my shares for me?

A:

No. If your shares of Midstates common stock or shares of Amplify common stock, as applicable, are held in the name of a broker, bank or other nominee, you will receive separate instructions from your broker, bank or other nominee describing how to vote your shares. The availability of Internet or telephonic voting will depend on the nominee's voting process. Please check with your broker, bank or other nominee and follow the voting procedures provided by your broker, bank or other nominee on your voting instruction form.

You should instruct your broker, bank or other nominee how to vote your shares of Midstates common stock or shares of Amplify common stock, as applicable. Under the rules applicable to broker-dealers, your broker, bank or other nominee does not have discretionary authority to vote your shares on any of the proposals scheduled to be voted on at the Amplify special meeting. A so-called "broker non-vote" results when banks, brokers and other nominees return a valid proxy voting upon a matter or matters for which the applicable rules provide discretionary authority but do not vote on a particular proposal because they do not have discretionary authority to vote on the matter and have not received specific voting instructions from the beneficial owner of such shares.

Midstates :    It is expected that each of the stock issuance proposal, the election of directors proposal, Midstates executive compensation proposal and the Midstates adjournment proposal are non-routine matters that brokers and nominees are not permitted to vote on absent specific instructions from the beneficial owner. However, the auditor ratification proposal is a routine matter that brokers and nominees are permitted to vote on absent specific instructions from the beneficial owner. Accordingly, if your broker submits a proxy for your shares of Midstates common stock with respect to the auditor ratification proposal but you do not provide specific instructions to your broker how to vote with respect to the stock issuance proposal, the election of directors proposal, the Midstates executive compensation proposal or the Midstates adjournment proposal, the proxy for your shares will be considered a broker non-vote for each such proposal. Broker non-votes are considered not entitled to vote on the stock issuance proposal, the election of directors proposal, the Midstates executive compensation proposal and the Midstates adjournment proposal and will therefore have no effect on the outcome of any of these proposals.

Amplify :    Amplify does not expect any broker non-votes at the Amplify special meeting because the rules applicable to banks, brokers and other nominees only provide brokers with discretionary authority to vote on proposals that are considered routine, whereas each of the proposals to be

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presented at the Amplify special meeting are considered non-routine. As a result, no broker will be permitted to vote your shares of Amplify common stock at the Amplify special meeting without receiving instructions. Failure to instruct your broker on how to vote your shares will have no effect on the outcome of the stock issuance proposal or the advisory compensation proposal, but will have the same effect as a vote "against" the approval of the merger agreement proposal.

Additional information on voting procedures can be found under "Midstates Annual Meeting" and under "Amplify Special Meeting."

Q:

What do I do if I am a Midstates stockholder and I want to revoke my proxy?

A:

Stockholders of record, other than those stockholders of record who are parties to voting agreements, may revoke their proxies at any time before their shares are voted at the Midstates annual meeting in any of the following ways:

•

sending a written notice of revocation to Midstates at 321 South Boston Avenue, Suite 1000, Tulsa, Oklahoma 74103, Attention: Corporate Secretary, which must be received before their shares are voted at the Midstates annual meeting;

•

properly submitting a later-dated, new proxy card, which must be received before their shares are voted at the Midstates annual meeting (in which case only the later-dated proxy is counted and the earlier proxy is revoked);

•

submitting a proxy via the Internet or by telephone at a later date, which must be received by 11:59 p.m., Eastern Time, on                     , 2019 (in which case only the later-dated proxy is counted and the earlier proxy is revoked); or

•

attending the Midstates annual meeting and voting in person. Attendance at the Midstates annual meeting will not, however, in and of itself, constitute a vote or revocation of a prior proxy.

Beneficial owners of Midstates common stock may change their voting instruction by submitting new voting instructions to the brokers, banks or other nominees that hold their shares of record or by requesting a "legal proxy" from such broker, bank or other nominee and voting in person at the Midstates annual meeting.

Additional information can be found under "Midstates Annual Meeting."

Q:

What do I do if I am an Amplify stockholder and I want to revoke my proxy?

A:

Stockholders of record, other than those stockholders of record who are parties to voting agreements, may revoke their proxies at any time before their shares are voted at the Amplify special meeting in any of the following ways:

•

sending a written notice of revocation to Amplify at 500 Dallas Street, Suite 1700, Houston, Texas 77002, Attention: Corporate Secretary, which must be received before their shares are voted at the Amplify special meeting;

•

properly submitting a later-dated, new proxy card, which must be received before their shares are voted at the Amplify special meeting (in which case only the later-dated proxy is counted and the earlier proxy is revoked);

•

submitting a proxy via the Internet or by telephone at a later date, which must be received by 11:59 p.m., Eastern Time, on                     , 2019 (in which case only the later-dated proxy is counted and the earlier proxy is revoked); or

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•

attending the Amplify special meeting and voting in person. Attendance at the Amplify special meeting will not, however, in and of itself, constitute a vote or revocation of a prior proxy.


Beneficial owners of Amplify common stock may change their voting instruction by submitting new voting instructions to the brokers, banks or other nominees that hold their shares of record or by requesting a "legal proxy" from such broker, bank or other nominee and voting in person at the Amplify special meeting.

Additional information can be found under "Amplify Special Meeting."

Q:

What happens if I sell or otherwise transfer my shares of Midstates common stock before the Midstates annual meeting?

A:

The record date for stockholders entitled to vote at the Midstates annual meeting is                    , 2019, which is earlier than the date of the Midstates annual meeting. If you sell or otherwise transfer your shares after the record date but before the Midstates annual meeting, unless special arrangements (such as provision of a proxy) are made between you and the person to whom you transfer your shares and each of you notifies us in writing of such special arrangements, you will retain your right to vote such shares at the Midstates annual meeting but will otherwise transfer ownership of your shares of Midstates common stock.

Q:

What happens if I sell or otherwise transfer my shares of Amplify common stock before the Amplify special meeting?

A:

The record date for stockholders entitled to vote at the Amplify special meeting is                    , 2019, which is earlier than the date of the Amplify special meeting. If you sell or otherwise transfer your shares after the record date but before the Amplify special meeting, unless special arrangements (such as provision of a proxy) are made between you and the person to whom you transfer your shares and each of you notifies us in writing of such special arrangements, you will retain your right to vote such shares at the Amplify special meeting but will otherwise transfer ownership of your shares of Amplify common stock.

Q:

What happens if I sell or otherwise transfer my shares of Amplify common stock before the completion of the merger?

A:

Only holders of shares of Amplify common stock at the effective time will become entitled to receive the merger consideration. If you sell your shares of Amplify common stock prior to the completion of the merger, you will not become entitled to receive the merger consideration by virtue of the merger.

Q:

Do any of the officers or directors of Amplify have interests in the merger that may differ from or be in addition to my interests as an Amplify stockholder?

A:

In considering the recommendation of the Amplify board that Amplify stockholders vote to adopt the merger agreement proposal and to approve the advisory compensation proposal, Amplify stockholders should be aware that some of Amplify's directors and executive officers have interests in the merger that may be different from, or in addition to, the interests of Amplify stockholders generally. The Amplify board was aware of and considered these potential interests, among other matters, in evaluating and negotiating the merger agreement and the transactions contemplated therein, in approving the merger and in recommending the adoption of the merger and the approval of the advisory compensation proposal.

For more information and quantification of these interests, please see "The Merger—Interests of Certain Amplify Directors and Executive Officers in the Merger."

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Q:

Do any of the officers or directors of Midstates have interests in the merger that may differ from or be in addition to my interests as a Midstates stockholder?

A:

In considering the recommendation of the Midstates board that Midstates stockholders vote to adopt the stock issuance proposal, Midstates stockholders should be aware that some of Midstates' directors and executive officers have interests in the merger that may be different from, or in addition to, the interests of Midstates stockholders generally. The Midstates board was aware of and considered these potential interests, among other matters, in evaluating and negotiating the merger agreement and the transactions contemplated therein, in approving the merger and in recommending the stock issuance proposal.

For more information and quantification of these interests, please see "The Merger—Interests of Certain Midstates Directors and Executive Officers in the Merger."

Q:

Where can I find voting results of the Midstates annual meeting and the Amplify special meeting?

A:

Midstates and Amplify intend to announce their respective preliminary voting results at each of the Midstates annual meeting and the Amplify special meeting and publish the final results in Current Reports on Form 8-K that will be filed with the SEC following the Midstates annual meeting and the Amplify special meeting, respectively. All reports that Midstates and Amplify file with the SEC are publicly available when filed. See "Where You Can Find More Information."

Q:

Do Midstates stockholders and Amplify stockholders have dissenters' rights or appraisal rights, as applicable?

A:

Midstates stockholders are not entitled to dissenters' or appraisal rights in connection with the merger under Section 262 of the Delaware General Corporate Law (the "DGCL").

Amplify stockholders are entitled to appraisal rights under Section 262 of the DGCL, provided they satisfy the special criteria and conditions set forth in Section 262 of the DGCL. Shares of Amplify common stock held by stockholders that do not vote for approval of the merger and make a demand for appraisal in accordance with Delaware law will not be converted into shares of Midstates common stock, but will be converted into the right to receive from the combined company consideration determined in accordance with Delaware law.

For further information relating to appraisal rights and dissenters' rights see "The Merger—Appraisal Rights and Dissenters' Rights."

Q:

Are there any risks that I should consider in deciding whether to vote for the adoption of the merger agreement or the stock issuance proposal?

A:

Yes. You should read and carefully consider the risk factors set forth in "Risk Factors," beginning on page 15 of this joint proxy statement/prospectus. You also should read and carefully consider the risk factors of Midstates and Amplify contained in the documents that are incorporated by reference into this joint proxy statement/prospectus.

Q:

How can I find more information about Midstates and Amplify?

A:

You can find more information about Midstates and Amplify from various sources as described in "Where You Can Find More Information."

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Q:

Who can answer any questions I may have about the Midstates annual meeting, the Amplify special meeting, the merger, or the transactions contemplated by the merger agreement, including the stock issuance?

A:

If you have any questions about the Midstates annual meeting, the Amplify special meeting, the merger, the stock issuance, or how to submit your proxy, or if you need additional copies of this joint proxy statement/prospectus or documents incorporated by reference herein, the enclosed proxy card or voting instructions, you should contact:

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