PRELIMINARY COPY — SUBJECT TO COMPLETION

MANNKIND CORPORATION

25134 Rye Canyon Loop,30930 Russell Ranch Road, Suite 300301

Valencia,Westlake Village, CA 9135591362

(661) 775-5300(818)661-5000

NOTICE OF ANNUALSPECIAL MEETING OF STOCKHOLDERS

To Be Held On Thursday, May 18,on Wednesday, December 13, 2017

Dear Stockholder:Stockholders:

You are cordially invited to attend the Annuala Special Meeting of Stockholders of MannKind Corporation, a Delaware corporation (“MannKind”).corporation. The meeting will be held on Thursday, May 18,Wednesday, December 13, 2017 at 10:00 a.m. U.S. Easternlocal time at the office of MannKind at 40 Taylor Street, Danbury, Connecticut 0681030930 Russell Ranch Road, Suite 301, Westlake Village, CA 91362.

We are holding the meeting for the following purposes:purposes, as more fully described in the accompanying proxy statement:

1. To electapprove an amendment to MannKind Corporation’s Amended and Restated Certificate of Incorporation to increase the seven nominees named herein as directorsauthorized number of shares of common stock from 140,000,000 shares to serve for the ensuing year and until their successors are elected;280,000,000 shares (the “Authorized Shares Increase Proposal”);

2. To approve, on an advisory basis,authorize the compensationadjournment of the named executive officers of MannKind, as disclosedmeeting, if necessary, to solicit additional proxies if there are insufficient votes in MannKind’s proxy statement for the Annual Meeting;

3. To indicate, on an advisory basis, the preferred frequency of stockholder advisory vote on the compensationfavor of the named executive officers of MannKind;

4. To ratify the selection by the Audit Committee of the Board of Directors of Deloitte & Touche LLP as the independent registered public accounting firm of MannKind for its fiscal year ending December 31, 2017;Authorized Shares Increase Proposal; and

5.3. To transact such other business as may properly come before the meeting or any adjournment or postponement thereof.

These itemsAll of business are more fully described in the proxy statement accompanying this notice.

The record date for the Annual Meeting is March 27, 2017. Onlyour stockholders of record on that date mayas of            , 2017 are entitled to attend and vote at the meeting orand at any adjournment or postponement thereof.

Our Board of Directors recommends that you vote FOR the Authorized Shares Increase Proposal as provided in Proposal 1 and FOR the authorization to adjourn the meeting, if necessary, to solicit additional proxies if there are not sufficient votes in favor of Proposal 1, as provided in Proposal 2.

By Order of the Board of Directors

David Thomson

Corporate Vice President, General Counsel and Secretary

Valencia,Westlake Village, California

April 7,November    , 2017

You are cordially invited to attend the meeting in person. Whether or not you expect to attend the meeting, please vote by proxy pursuant to the instructions set forth herein as promptly as possible in order to ensure your representation at the meeting. Even if you have voted by proxy, you may still vote in person if you attend the meeting. Please note, however, that if your shares are held of record by a broker, bank or other nominee and you wish to vote at the meeting, you must obtain a proxy issued in your name from that record holder.

All visitors to the MannKind DanburyWestlake Village site will be required to present a government-issued photo identification. Thank you, in advance, for your cooperation.

PRELIMINARY COPY — SUBJECT TO COMPLETION

MANNKIND CORPORATION

25134 Rye Canyon Loop,30930 Russell Ranch Road, Suite 300301

Valencia, California 91355Westlake Village, CA 91362

PROXY STATEMENT

FOR THE 2017 ANNUALA SPECIAL MEETING OF STOCKHOLDERS

To be held on May 18,December 13, 2017

QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS AND VOTING

Why did I receive these proxy materials?

We have sent you this proxy statement and the enclosed proxy card because the Board of Directors (sometimes referred to as the “Board” or the “Board of Directors”) of MannKind Corporation (sometimes referred to as the “Company,” “MannKind,” “we” or “us”) is soliciting your proxy to vote at a notice regardingSpecial Meeting of Stockholders (the “Special Meeting”), including any adjournments or postponements of the availability of proxy materials on the internet?

Special Meeting. Pursuant to rules adopted by the Securities and Exchange Commission (the “SEC”), we have elected to provideare also providing access to our proxy materials over the internet. Accordingly, we have sent you a Notice of Internet Availability of Proxy Materials (the “Notice”) because the Board of Directors (sometimes referredinternet, which can be accessed at www.proxypush.com/mnkd.

We intend to as the “Board”) of MannKind Corporation (sometimes referred to as, “we,” “us,” the “Company” or “MannKind”) is soliciting your proxy to vote at the 2017 Annual Meeting of Stockholders (the “Annual Meeting”), including any adjournments or postponements of the Annual Meeting. You are invited to attend the annual meeting to vote on the proposals described in this proxy statement. However, you do not need to attend the meeting to vote your shares. All stockholders will have the ability to access themail these proxy materials on the website referredor about November     , 2017 to in the Notice or request to receive a printed set of the proxy materials. Instructions on how to access the proxy materials over the internet or to request a printed copy may be found in the Notice.

The Notice is expected to be first mailed to ourall stockholders of record entitled to vote at the Annual Meeting on or about April 7, 2017.

Will I receive any other proxy materials by mail?

We may send you a proxy card, along with a second Notice, on or after April 17, 2017.Special Meeting.

Who can vote at the AnnualSpecial Meeting?

Only stockholders of record at the close of business on             March 27,, 2017 (the “record date”) will be entitled to vote at the Annual Meeting.Special Meeting or any adjournment or postponement thereof. On thisthe record date, there were 95,776,246            shares of common stock outstanding and entitled to vote.

Stockholder of Record: Shares Registered in Your Name

If on March 27, 2017the record date your shares were registered directly in your name with MannKind’s transfer agent, Computershare Inc., then you are a stockholder of record. As a stockholder of record, you may vote in person at the meetingSpecial Meeting or vote by proxy. Whether or not you plan to attend the AnnualSpecial Meeting, we urge you to vote by proxy pursuant to the instructions set forth below to ensure your vote is counted.

Beneficial Owner: Shares Registered in the Name of a Broker or Bank

If on March 27, 2017the record date your shares were held, not in your name, but rather in an account at a brokerage firm, bank, dealer, or other similar organization, then you are the beneficial owner of shares held in “street name” and Notice isthese proxy materials are being forwarded to you by that organization. The organization holding your account is considered to be the stockholder of record for purposes of voting at the AnnualSpecial Meeting. As a beneficial owner, you have the right to direct your broker or other agent on how to vote the shares in your account. You are also invited to attend the AnnualSpecial Meeting. However, because you are not the stockholder of record, you may not vote your shares in person at the AnnualSpecial Meeting unless you request and obtain a valid proxy from your broker or other agent.

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What am I voting on?

Management is presenting fourtwo proposals for stockholder vote.

Proposal 

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1. ElectionTo amend MannKind’s Amended and Restated Certificate of Seven DirectorsIncorporation to increase the authorized number of shares of our common stock from 140,000,000 shares to 280,000,000 shares (the “Authorized Shares Increase Proposal”).

The first proposal to be voted on is2. To approve the electionadjournment of the seven nominees named herein as directorsSpecial Meeting for a one-year term. The Board has nominated these seven people as directors. You may find information about these nominees, as well as information about MannKind’s Boardany purpose, including to solicit additional proxies if there are insufficient votes at the time of Directors and its committees, director compensation and other related matters beginning on page 7.the Special Meeting to approve the Authorized Shares Increase Proposal (the “Adjournment Proposal”).

YouFor each proposal, you may vote “For” all the nominees, “Withhold” your votes as to all nominees or “Withhold” your votes as to specific nominees.

The Board of Directors unanimously recommends asuch proposal, vote FOR all the director nominees named herein.

Proposal 2. Advisory Vote on Executive Compensation

The second proposal to be voted on is an advisory vote by the stockholders of MannKind regarding the compensation of the Company’s named executive officers as described in this proxy statement, including the disclosures under “Compensation Discussion and Analysis,” the compensation tables and the narrative discussion following the compensation tables. The Company is seeking the stockholders’ approval, on an advisory basis, of the compensation of the named executive officers. You may find information about this proposal beginning on page 16.

You may vote “For” or “Against” thesuch proposal or “Abstain” from voting on thesuch proposal.

The Board of Directors unanimously recommends a vote FOR Proposal 2.

Proposal 3. Advisory Indication on the Preferred Frequency of Stockholder Advisory Vote on Executive Compensation

The third proposal is an advisory vote on the frequency of solicitation of stockholder approval of executive compensation.

Stockholders are provided with the opportunity to choose among four options (holding the vote every one, two or three years, or abstaining) and, therefore, stockholders will not be voting to approve or disapprove the recommendationeach of the Board of Directors. The option among those choices that obtains a majority of votes cast by the shares present or represented by proxy and entitled to vote at the Annual Meeting will be deemed to be the frequency adopted for advisory purposes by our stockholders in accordance with our Amended and Restated Bylaws; however, in the event that no frequency receives a majority, we will consider whichever frequency receives a plurality of the votes to be the frequency preferred by our stockholders. You may find information about this proposal on page 18.

The Board and the Compensation Committee value the opinions of our stockholders in this matter, and the Board of Directors intends to hold say-on-pay votes in the future in accordance with the alternative that receives the most stockholder support.

The Board of Directors unanimously recommends one year as the preferred frequency of stockholder advisory vote on executive compensation.

Proposal 4. Ratification of Selection by the Audit Committee of the Board of Directors of Deloitte & Touche LLP as the Company’s Independent Registered Public Accounting Firm for the Fiscal Year Ending December 31, 2017

The fourth proposal to be voted on is to ratify the selection by the Audit Committee of the Board of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for the fiscal year

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ending December 31, 2017. It is expected that representatives of Deloitte & Touche LLP will attend the Annual Meeting and be available to make a statement or respond to appropriate questions. You may find information about this proposal beginning on page 19.

You may vote “For” or “Against” the proposal or “Abstain” from voting on the proposal.

The Board of Directors unanimously recommends a vote FOR Proposal 4.foregoing proposals.

What if another matter is properly brought before the AnnualSpecial Meeting?

The Board of Directors knows of no other matters that will be presented for consideration at the AnnualSpecial Meeting. If any other matters are properly brought before the AnnualSpecial Meeting, it is the intention of the persons named in the proxy to vote on those matters in accordance with their best judgment.

How do I vote?

The procedures for voting are fairly simple:

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record, you may vote in person at the AnnualSpecial Meeting or vote by proxy using the enclosed proxy card, vote by proxy over the telephone or vote by proxy through the internet or vote by proxy using a proxy card that you may request or that we may elect to deliver at a later time.internet. Whether or not you plan to attend the AnnualSpecial Meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the AnnualSpecial Meeting and vote in person if you have already voted by proxy.

We provide internet proxy voting to allow you to vote your shares online, with procedures designed to ensure the authenticity and correctness of your proxy vote instructions. However, please be aware that you must bear any costs associated with your internet access, such as usage charges from internet access providers and telephone companies.

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Beneficial Owner: Shares Registered in the Name of Broker or Bank

If you are a beneficial owner of shares registered in the name of your broker, bank, or other agent, you should have received a Notice containingproxy card and voting instructions with this proxy statement from that organization rather than from MannKind. Simply followcomplete and mail the proxy card as directed by the voting instructions in the Notice to ensure that your vote is counted. Alternatively, you may be able to vote by telephone or over the Internet as instructed by your broker or bank. To vote in person at the AnnualSpecial Meeting, you must obtain a valid proxy from your broker, bank, or other agent. Follow the instructions from your broker or bank included with theseour proxy materials, or contact your broker or bank to request a proxy form.

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How many votes do I have?

On each matter to be voted upon, you have one vote for each share of common stock you owned as of March 27, 2017.the record date.

What if I return a proxy card or otherwise vote by proxy but do not make specific choices?

If you voted by proxy without marking any voting selections, your shares will be voted “For”then the election of each of the seven nominees for director listed in Proposal 1, “For” the advisory approval of the executive compensation of the Company’s named executive officers as provided in Proposal 2, “For” one year as the preferred frequency of stockholder advisory vote on executive compensation as provided in Proposal 3 and “For” the ratification of the selection of Deloitte & Touche LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2017 as provided in Proposal 4. If any other matter is properly presented at the Annual Meeting, your proxy (one of the individuals named on your proxy card)holders will vote your shares using his or her best judgment.as recommended by the Board on all matters presented in this Proxy Statement, and as the proxy holders may determine in their discretion with respect to any other matters properly presented for a vote at the Special Meeting

Who is paying for this proxy solicitation?

We will pay for the entire cost of soliciting proxies. In addition to these proxy materials, our directors and employees may also solicit proxies in person, by telephone, or by other means of communication. Directors and employees will not be paid any additional compensation for soliciting proxies. We will also reimburse brokerage firms, banks and other agents for the cost of forwarding proxy materials to beneficial owners.

In addition, we have retained Morrow & Co. to assist in the solicitation. We will pay Morrow Sodali LLC approximately $9,500 plusout-of-pocket expenses, for its assistance.

What does it mean if I receive more than one Notice?proxy card?

If you receive more than one Notice,proxy card, your shares are registered in more than one name or are registered in different accounts. Please follow the voting instructions with respect toeachNotice to ensure that all of your shares are voted. Similarly, if you are a stockholder of record and you receive more than one Notice, your shares are registered in more than one name. Please follow the voting instructions with respect toeachNoticeproxy card to ensure that all of your shares are voted.

Can I change my vote after submitting my proxy?

Yes. You can revoke your proxy at any time before the final vote at the AnnualSpecial Meeting. If you are a stockholder of record, you may revoke your proxy in any one of the following ways:

Your most current proxy, whether submitted by proxy card, telephone or internet, is the one that is counted.

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If your shares are held by your broker or bank as a nominee or agent, you should follow the instructions provided by your broker or bank.

How are votes counted?

Votes will be counted by the inspector of election appointed for the meeting,Special Meeting, who will separately count with respect to the proposal to elect directors, votes “For,” “Withhold” and broker non-votes; with respect to the

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proposal regarding frequency of stockholder advisory votes to approve executive compensation, votes for frequencies of one year, two years or three years, abstentions and broker non-votes; and with respect to other proposals, “For” and “Against” votes, abstentions and, if applicable,any, brokernon-votes. Abstentions will be counted towards the vote total for each of Proposals 2 and 4,proposal, and will have the same effect as “Against” votes. For Proposal 3, abstentionsBrokernon-votes will be counted towards the vote total, and willalso have the same effect as votes against each of the proposed voting frequencies. Broker non-votes will have no effect and will not be counted towards the vote total for any proposal.“Against” votes.

What are “brokernon-votes”?

Brokernon-votes occur when a beneficial owner of shares held in street name does not give instructions to the broker or nominee holding the shares as to how to vote on matters deemed “non-routine.“non-routine.” Generally, if shares are held in street name (shares are held by your broker as your nominee), the beneficial owner of the shares is entitled to give voting instructions to the broker or nominee holding the shares. If you do not give instructions to your broker, your broker can vote your shares with respect to matters that are considered to be “routine,” but not with respect to “non-routine”“non-routine” matters. Under the rules and interpretations of the New York Stock Exchange, “non-routine”“non-routine” matters are generally those involving a contest or a matter that may substantially affect the rights or privileges of stockholders, such as mergers or stockholder proposals, election of directors (even if not contested)stockholders. The Authorized Shares Increase Proposal and executive compensation, including the stockholder advisory votes on executive compensation. Proposals 1, 2 and 3 regarding the election of directors, the advisory vote regarding executive compensation and advisory indication on the preferred frequency of stockholder advisory vote on executive compensationAdjournment Proposal are non-routineboth considered routine matters. Proposal 4 to ratify Deloitte & Touche LLP as our independent registered public accounting firm is a routine matter.

How many votes are needed to approve each proposal?the Authorized Shares Increase Proposal?

ForTo be approved, the election of directors, the seven nominees receiving the mostAuthorized Shares Increase Proposal must receive “For” votes (among votes properly cast in person or by proxy) will be elected. Only votes “For” or “Withhold” will affectfrom the outcome. Only the seven nominees named herein have been properly nominated for election as directors.

Proposals 2 and 4 regarding, respectively, approval on an advisory basisholders of the compensationa majority of the Company’s named executive officers and ratification ofcommon stock having voting power outstanding on the Audit Committee’s selection ofrecord date for the independent registered public accounting firm, must receive a “For” vote from the majority of shares present and entitled to vote either in person or by proxy in order to be approved.Special Meeting. If you “Abstain” from voting, it will have the same effect as an “Against” vote. Brokernon-votes, if any, will also have no effect.the same effect as “Against” votes.

For Proposal 3, stockholdersHow many votes are provided with the opportunity to choose among four options (holding the vote every one, two or three years, or abstaining) and, therefore, stockholders will not be votingneeded to approve or disapprove the recommendation ofAdjournment Proposal?

To be approved, the Board of Directors. The option among those choices that obtainsAdjournment Proposal must receive “For” votes from a majority of votes cast by the shares of our common stock present or represented by proxy at the Special Meeting and entitled to vote aton such matter. If you “Abstain” from voting, it will have the Annual Meetingsame effect as an “Against” vote. Brokernon-votes, if any, will be deemed to bealso have the frequency adopted for advisory purposes by our stockholders in accordance with our Amended and Restated Bylaws; however, in the event that no frequency receives a majority, we will consider whichever frequency receives a plurality of the votes to be the frequency preferred by our stockholders. The Board and the Compensation Committee value the opinions of our stockholders in this matter, and the Board of Directors intends to hold say-on-pay votes in the future in accordance with the alternative that receives the most stockholder support.same effect as “Against” votes.

What is the quorum requirement?

A quorum of stockholders is necessary to hold a valid AnnualSpecial Meeting. A quorum will be present if at least a majority of the outstanding shares entitled to vote are represented by stockholders present at the AnnualSpecial Meeting or by proxy. On the record date, there were            95,776,246 shares outstanding and entitled to vote. Thus, 47,888,124            shares must be represented by stockholders present at the AnnualSpecial Meeting or by proxy to have a quorum.

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Your shares will be counted towards the quorum only if you submit a valid proxy (or one is submitted on your behalf by your broker, bank or other nominee) or if you vote in person at the AnnualSpecial Meeting. Abstentions and brokernon-votes will be counted towards the quorum requirement. If there is no quorum, the chairman of the AnnualSpecial Meeting or a majority of the votes present at the AnnualSpecial Meeting may adjourn the meeting to another date.

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How can I find out the results of the voting at the AnnualSpecial Meeting?

Preliminary voting results will be announced at the AnnualSpecial Meeting. Final voting results will be published in a current reporton Form 8-K that we expect to file no later than four business days followingafter the dateconclusion of the AnnualSpecial Meeting. If final voting results are not available to us in time to filea Form 8-K on or before such date,the fourth business day after the Special Meeting, we intend to filea Form 8-K to publish preliminary results and, within four business days after the final results are known to us, file anadditional Form 8-K to publish the final results.

When are stockholder proposals due for next year’s annual meeting?

To be considered for inclusion in MannKind’s proxy material for next year’s annual meeting, your proposal must be submitted in writing by December 8, 2017 to Attn: Corporate Secretary, MannKind Corporation, 25134 Rye Canyon Loop,30930 Russell Ranch Road, Suite 300, Valencia,301, Westlake Village, CA 91355.91362. If you wish to submit a proposal that is not to be included in MannKind’s proxy materials or nominate a director, you must do so not later than February 17, 2018 and not earlier than January 18, 2018. You are also advised to review the Company’s Amended and Restated Bylaws, which contain additional requirements about advance notice of stockholder proposals and director nominations.

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PROPOSAL 1

ELECTIONAPPROVAL OF DIRECTORS

MannKind’s Board of Directors consists of seven directors. There are seven nominees for director this year, all of whom were nominated by our Board of Directors. Each director to be elected will hold office until the next annual meeting of stockholders and until his successor is elected, or until the director’s earlier death, resignation or removal. All nominees listed below are currently our directors and were previously elected by our stockholders at the 2016 Annual Meeting of Stockholders. It is our policy that directors are invited and expected to attend annual meetings. All directors attended the 2016 Annual Meeting of Stockholders.

Directors are elected by a plurality of the votes properly cast in person or by proxy. The seven nominees receiving the highest number of affirmative votes will be elected. Shares represented by executed proxies will be voted, if authority to do so is not withheld, for the election of the seven nominees named below. If any nominee becomes unavailable for election as a result of an unexpected occurrence, your shares may be voted for the election of a substitute nominee proposed by our Nominating and Corporate Governance Committee. Each person nominated for election has agreed to serve if elected. Our management has no reason to believe that any nominee will be unable to serve.

NOMINEES

The following is a brief biography of each nominee for director and a discussion of the specific experience, qualifications, attributes or skills of each nominee that led our Board of Directors to conclude that each nominee should serve as a member of the Board.

Kent Kresa has been a member of our Board of Directors since June 2004 and has served as Chairman of the Board since February 2017. From November 2011 until his appointment as our Chairman, Mr. Kresa served on our Board of Directors as our lead independent director. Mr. Kresa is Chairman Emeritus of Northrop Grumman Corporation, a defense company and from September 1990 until October 2003, he was also its Chairman. He also served as Chief Executive Officer of Northrop Grumman Corporation from January 1990 until March 2003 and as its President from 1987 until September 2001. From 2003 to August 2010, Mr. Kresa served as a director of General Motors Company (or its predecessor). From December 2005 to April 2010, Mr. Kresa served as a director of Avery Dennison Corporation. Mr. Kresa has been a member of the Caltech Board of Trustees since 1994. Mr. Kresa has served on the board of Fluor Corporation since 2003, and he also serves on the boards of several non-profit organizations and universities. As a graduate of Massachusetts Institute of Technology, he received a B.S. in 1959, an M.S. in 1961, and an E.A.A. in 1966, all in aeronautics and astronautics. The Board believes that Mr. Kresa’s business experience, including his experience as a director and executive officer of Northrop Grumman, and his service on other public company boards, combined with his business acumen and judgment provide our Board with valuable operational expertise and leadership and qualifies him to serve on our Board of Directors.

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Matthew J. Pfefferhas served as our Chief Executive Officer and as one of our directors since January 2016, and as our Chief Financial Officer since April 2008. Mr. Pfeffer also served as a Corporate Vice President from April 2008 until January 2016. Previously, Mr. Pfeffer served as Chief Financial Officer and Senior Vice President of Finance and Administration of VaxGen, Inc. from March 2006 until April 2008, with responsibility for finance, tax, treasury, human resources, IT, purchasing and facilities functions. Prior to VaxGen, Mr. Pfeffer served as Chief Financial Officer of Cell Genesys, Inc. During his nine year tenure at Cell Genesys, Mr. Pfeffer served as Director of Finance before being named Chief Financial Officer in 1998. Prior to that, Mr. Pfeffer served in a variety of financial management positions at other companies, including roles as Corporate Controller, Manager of Internal Audit and Manager of Financial Reporting. Mr. Pfeffer began his career at Price Waterhouse. Currently, Mr. Pfeffer serves on the board of directors of Second Sight Medical Products in Sylmar, California. Mr. Pfeffer graduated from the University of California, Berkeley and is a Certified Public Accountant. The Board believes that Mr. Pfeffer’s knowledge and understanding of accounting and finance and his extensive experience with our company, combined with his business acumen and judgment, provide our Board with valuable accounting, financial and operational expertise and leadership and qualifies him to serve on our Board of Directors.

Ronald J. Consiglio has been one of our directors since October 2003. Since 1999, Mr. Consiglio has been the managing director of Synergy Trading, a securities-trading partnership. From 1999 to 2001, Mr. Consiglio was Executive Vice President and Chief Financial Officer of Trading Edge, Inc., a national automated bond-trading firm. From January 1993 to 1998 Mr. Consiglio served as Chief Executive Officer of Angeles Mortgage Investment Trust, a publicly traded Real Estate Investment Trust. His prior experience includes serving as Senior Vice President and Chief Financial Officer of Cantor Fitzgerald & Co. and as a member of its board of directors. Mr. Consiglio has served as a member of the board of trustees for the Metropolitan West Funds since 2003. Mr. Consiglio is a certified public accountant and holds a bachelor’s degree in accounting from California State University at Northridge. The Board believes that Mr. Consiglio’s knowledge and understanding of accounting and finance, his experience as a board member and executive officer at financial services firms, combined with his business acumen and judgment provide our Board with valuable accounting, financial and operational expertise and leadership and qualifies him to serve on our Board of Directors.

Michael A. Friedman, M.D.has been one of our directors since December 2003. In 2014, Dr. Friedman completed a decade of service as the President and Chief Executive Officer of the City of Hope National Medical Center. Previously, from September 2001 until April 2003, Dr. Friedman held the position of Senior Vice President of Research and Development, Medical and Public Policy, for Pharmacia Corporation and, from July 1999 until September 2001, was a senior vice president of Searle, a subsidiary of Monsanto Company. From 1995 until June 1999, Dr. Friedman served as Deputy Commissioner for Operations for the Food and Drug Administration, and was Acting Commissioner and Lead Deputy Commissioner from 1997 to 1998. He joined the board of Celgene Corporation in February 2011 and the board of Smith & Nephew plc in April 2013. Dr. Friedman received a bachelor of arts degree, magna cum laude, from Tulane University, New Orleans, Louisiana, and a doctorate in medicine from the University of Texas, Southwestern Medical School. The Board believes Dr. Friedman’s business experience, including his experience as an executive officer at biopharmaceutical companies and a leading clinical and research center specializing in cancer and diabetes, and his service at the Food and Drug Administration, combined with his business acumen and judgment provide our Board with valuable scientific and operational expertise and leadership and qualifies him to serve on our Board of Directors.

David H. MacCallum has been one of our directors since June 2004. Since 2002, Mr. MacCallum has served as the Managing Partner of Outer Islands Capital, a hedge fund specializing in health care investments. From June 1999 until November 2001, he was Global Head of Health Care investment banking for Salomon Smith Barney, part of Citigroup, a financial institution. Prior to joining Salomon Smith Barney, he was Executive Vice President and Head of the Health Care group at ING Barings Furman Selz LLC, an investment banking firm and subsidiary of ING Group, a Dutch financial institution, from April 1998 to June 1999. Prior to that, Mr. MacCallum formed the Life Sciences group at UBS Securities, an investment banking firm, where he was

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Managing Director and Global Head of Life Sciences from May 1994 to April 1998. Before joining UBS Securities, he built the health care practice at Hambrecht & Quist, an investment banking firm, where he was Head of Health Care and Co-Head of Investment Banking. From 2005 to October 2010, Mr. MacCallum served as a director of Zymogenetics, Inc. From 2002 to 2008, he served as a director of Vital Signs, Inc. Mr. MacCallum received an A.B. degree from Brown University and an M.B.A. degree from New York University. He is a Chartered Financial Analyst. The Board believes that Mr. MacCallum’s knowledge and understanding of accounting and finance, his business experience in the investment banking industry, combined with his business acumen and judgment provide our Board with valuable accounting, financial and operational expertise and leadership and qualifies him to serve on our Board of Directors.

Henry L. Nordhoff has been one of our directors since March 2005. He has served as a director of BioTime, Inc. since June 2013 and as a director of Asterias Biotherapeutics, Inc. since October 2013. Mr. Nordhoff retired as Chairman of the Board of Gen-Probe Incorporated, a clinical diagnostic and blood screening company, at the end of 2011, after serving as its Chairman since September 2002. He also served as Chief Executive Officer and President of Gen-Probe from July 1994 until May 2009. Prior to joining Gen-Probe, he was President and Chief Executive Officer of TargeTech, Inc., a gene therapy company that was merged into Immune Response Corporation. Prior to that, Mr. Nordhoff was at Pfizer, Inc. in senior positions in Brussels, Seoul, Tokyo and New York. He received a B.A. in international relations and political economy from Johns Hopkins University and an M.B.A. from Columbia University. The Board believes that Mr. Nordhoff’s business experience, including his experience as a director and executive officer at pharmaceutical and biotech companies, combined with his business acumen and judgment provide our Board with valuable operational expertise and leadership and qualifies him to serve on our Board of Directors.

James S. Shannon,M.D., MRCP (UK) rejoined our board in May 2015 after previously serving as a director from February 2010 until April 2012. From May 2012 until his retirement in April 2015, Dr. Shannon was the Chief Medical Officer of GlaxoSmithKline. He formerly held the position of Global Head of Pharma Development at Novartis AG, based in Basel, Switzerland from 2005 until 2008. After joining Sandoz in 1994 as Head of Drug Regulatory Affairs, Dr. Shannon led the Integration Office for R&D overseeing the creation of the Novartis R&D groups from those of Ciba-Geigy Ltd and Sandoz. Following the merger he was appointed Head of the Cardiovascular Strategic Team and subsequently became Global Head of Project Management before being appointed Global Head of Clinical Development and Medical Affairs in 1999, a position that he held until 2005 when he was appointed to Head Pharma Development. Between 2008 and joining GSK, Dr. Shannon served on the boards of a number of companies, including Biotie, Circassia, Crucell, Endocyte and MannKind. He also sat on the board of Cerimon Pharmaceuticals where he held the position of interim Chief Executive Officer and President from January 2009 until April 2010. He first entered the pharmaceutical industry in 1987 joining Sterling Winthrop Inc., working initially in Europe and subsequently in the USA, where he held positions of increasing responsibility in the management of research and development ultimately serving as Senior Vice-President, Clinical Development. Dr. Shannon is trained in Medicine and Cardiology. He received his undergraduate and postgraduate degrees at Queen’s University of Belfast and is a Member of the Royal College of Physicians (UK). The Board believes that Dr. Shannon’s business experience and his extensive experience in drug development, combined with his business acumen and judgment provide our Board with valuable scientific and operational expertise and leadership and qualifies him to serve on our Board of Directors.

THE BOARDINCREASE IN NUMBER OF DIRECTORS RECOMMENDS

AVOTEFORTHE ELECTION AUTHORIZED SHARES OFALL DIRECTOR NOMINEESNAMEDABOVE

CORPORATE GOVERNANCE PRINCIPLES AND BOARD AND COMMITTEE MATTERS

INDEPENDENCEOFTHE BOARDOF DIRECTORS

As required under the Nasdaq Stock Market (“Nasdaq”) listing standards, a majority of the members of a listed company’s board of directors must qualify as “independent,” as affirmatively determined by the board of

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directors. Our Board of Directors consults with the Company’s counsel to ensure that the Board’s determinations are consistent with all relevant securities and other laws and regulations regarding the definition of “independent,” including those set forth in pertinent listing standards of Nasdaq, as in effect time to time.

Consistent with these considerations, after review of all relevant transactions or relationships between each director or any of his family members and the Company, its senior management and its independent auditors, the Board of Directors affirmatively has determined that all of the Company’s directors other than Mr. Pfeffer is independent within the meaning of the applicable Nasdaq listing standards. In making this determination, the Board found that none of the directors has a material or other disqualifying relationship with the Company.

INFORMATION REGARDINGTHE BOARDOF DIRECTORSANDITS COMMITTEES

We are committed to maintaining the highest standards of business conduct and ethics. Our Board of Directors has adopted a Code of Business Conduct and Ethics and adheres to corporate governance guidelines to assure that the Board will have the necessary authority and practices in place to review and evaluate our business operations as needed and to make decisions that are independent of our management. The guidelines are also intended to align the interests of directors and management with those of our stockholders. The charters for various Board committees set forth the practices the Board will follow with respect to board composition and selection, board meetings and involvement of senior management, Chief Executive Officer performance evaluation and succession planning, and board committees and compensation. Our Board of Directors adopted these measures to, among other things, reflect changes to the Nasdaq listing standards and SEC rules adopted to implement provisions of the Sarbanes-Oxley Act of 2002, as amended. Our Code of Business Conduct and Ethics, as well as the charters for each committee of the Board, may be viewed on our website atwww.mannkindcorp.com.

BOARD LEADERSHIP STRUCTURE

Our Board of Directors is currently chaired by Mr. Kresa. As a general policy, our Board of Directors believes that separation of the positions of Chairman and Chief Executive Officer reinforces the independence of the Board of Directors from management, creates an environment that encourages objective oversight of management’s performance and enhances the effectiveness of the Board of Directors as a whole. As such, Mr. Pfeffer serves as our Chief Executive Officer while Mr. Kresa serves as our Chairman of the Board of Directors but is not an officer. We expect and intend the positions of Chairman of the Board of Directors and Chief Executive Officer to continue to be held by separate individuals in the future. If in the future we conclude there is a compelling reason for the positions of Chairman of the Board and Chief Executive Officer to be occupied by the same individual, we would except to appoint one of our other directors to the position of lead independent director to help reinforce the independence of the Board from management.

ROLEOFTHE BOARDIN RISK OVERSIGHT

One of the key functions of our Board of Directors is informed oversight of the Company’s risk management process. The Board of Directors does not have a standing risk management committee, but rather administers this oversight function directly through the Board as a whole, as well as through various standing committees that address risks inherent in their respective areas of oversight. In particular, our Board is responsible for monitoring and assessing strategic risk exposure, including a determination of the nature and level of risk appropriate for the Company. Our Audit Committee has the responsibility to consider and discuss our major financial risk exposures and the steps our management has taken to monitor and control these exposures, including guidelines and policies to govern the process by which risk assessment and management is undertaken. Our Compensation Committee reviews and approves individual and corporate performance goals, advises the Board regarding the adoption, modification, or termination of compensation plans and policies and assesses and monitors whether any of our compensation policies and programs has the potential to encourage excessive risk-taking.

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COMMITTEESOFTHE BOARDOF DIRECTORS COMMON STOCK

The Board of Directors has three standing committees:is requesting stockholder approval of an Audit Committee, a Compensation Committee,amendment to the Company’s Amended and a Nominating and Corporate Governance Committee. All three committees operate under written charters adopted by ourRestated Certificate of Incorporation to increase the Company’s authorized number of shares of common stock from 140,000,000 to 280,000,000 shares. The form of amendment is attached to this proxy statement as Appendix A.

As of                     , 2017, in addition to the              shares of common stock outstanding, the Board all of which are available on our website atwww.mannkindcorp.com.

Eachhad reserved              of the committees has authority to engage legal counsel or other experts or consultants, as it deems appropriate to carry out its responsibilities. The Board of Directors has determined that each member of each committee meets the applicable rulesremaining authorized and regulations regarding “independence” and that each member is free of any relationship that would interfere with his or her individual exercise of independent judgment with regard to the Company. Below is a description of each committee.

Audit Committee

Our Audit Committee consists of Mr. Consiglio (chair), Mr. MacCallum and Mr. Nordhoff, each of whom is an independent member of our Board of Directors (as determined by our Board based on its annual review of the independence requirement of Audit Committee members provided in Rule 5605(c)(2)(A)(i) and (ii) of the Nasdaq listing standards). Our Audit Committee was established by the Board in accordance with Section 3(a)(58)(A) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), to oversee the Company’s corporate accounting and financial reporting processes and audits of its financial statements. The functions of this committee include, among others:

The Board of Directors has determined that Mr. Consiglio qualifies as an “audit committee financial expert,” as that term is defined in applicable SEC rules. In making such determinations, the Board of Directors made a qualitative assessment of Mr. Consiglio’s level of knowledge and experience based on a number of factors, including his formal education and experience. Both our independent registered public accounting firm and internal financial personnel regularly meet privately with our Audit Committee and have unrestricted access to this committee. Our Audit Committee charter can be found on our corporate website atwww.mannkindcorp.com.The Audit Committee met eleven times during 2016. The report of the Audit Committee is included herein on page 47.

Compensation Committee

Our Compensation Committee consists of Mr. Kresa (chair), Dr. Friedman and Dr. Shannon, each of whom is an independent member of our Board of Directors (as independence is currently defined in Rule 5605(a)(2) of the Nasdaq listing standards). The functions of this committee include, among others:

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Typically, the Compensation Committee meets at least quarterly and with greater frequency if necessary. The Compensation Committee met four times during 2016.

The processes and procedures of the Compensation Committee with respect to executive compensation are described in greater detail in the “Compensation Discussion and Analysis” section of this proxy statement. Our Compensation Committee charter can be found on our corporate website atwww.mannkindcorp.com.The report of the Compensation Committee is included herein on page 46.

Nominating and Corporate Governance Committee

Our Nominating and Corporate Governance Committee consists of Dr. Friedman (chair), Mr. Consiglio and Mr. Kresa, each of whom is an independent member of our Board of Directors (as independence is currently defined in Rule 5605(a)(2) of the Nasdaq listing standards). The functions of this committee include, among others:

Our Nominating and Corporate Governance Committee charter can be found on our corporate website atwww.mannkindcorp.com.The Nominating and Corporate Governance Committee did not meet during 2016.

CONSIDERATIONOF DIRECTOR NOMINEES

Director Qualifications

The Nominating and Corporate Governance Committee believes that candidates for director should have certain minimum qualifications, including being able to read and understand basic financial statements, being over 21 years of age and having the highest personal integrity and ethics. The Nominating and Corporate Governance Committee also intends to consider such factors as possessing relevant expertise upon which to be

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able to offer advice and guidance to management, having sufficient time to devote to the affairsunissued shares of the Company demonstrated excellence in hisfor issuances under the Company’s equity incentive plans, upon exercise of outstanding warrants or her field, having the abilityupon conversion of an outstanding convertible note.

The additional common stock to exercise sound business judgment and having the commitment to rigorously represent the long-term interestsbe authorized by adoption of the Company’s stockholders. However,amendment would have rights identical to the Nominating and Corporate Governance Committee retains the discretion to modify these qualifications from time to time.

Evaluating Nominees for Director

The Nominating and Corporate Governance Committee review candidates for director nominees in the contextcurrently outstanding common stock of the current composition of the Board of Directors, the operating requirements of the Company and the long-term interests of the Company’s stockholders. In conducting this assessment, the Nominating and Corporate Governance Committee considers age, skills, and such other factors as it deems appropriate given the current needs of the Board of Directors and the Company, to maintain a balance of knowledge, experience and capability. In the case of incumbent directors, the Nominating and Corporate Governance Committee reviews such directors’ overall service to the Company during their term, including the number of meetings attended, level of participation, quality of performance, and any other relationships and transactions that might impair such directors’ independence. In the case of new director candidates, the Nominating and Corporate Governance Committee also determines whether the nominee would be independent for Nasdaq purposes, which determination is based upon applicable Nasdaq listing standards, applicable SEC rules and regulations and the advice of counsel, if necessary. The Nominating and Corporate Governance Committee also focuses on issues of diversity, such as diversity of gender, race and national origin, education, professional experience and differences in viewpoints and skills. The Nominating and Corporate Governance Committee does not have a formal policy with respect to diversity; however, the Board of Directors and the Nominating and Corporate Governance Committee believe that it is important that directors represent diverse viewpoints.

The Nominating and Corporate Governance Committee uses its network of contacts to compile a list of potential candidates, but may also engage, if it deems appropriate, a professional search firm. The Nominating and Corporate Governance Committee conducts any appropriate and necessary inquiries into the backgrounds and qualifications of possible candidates after considering the function and needs of the Board. The Nominating and Corporate Governance Committee meets to discuss and consider such candidates’ qualifications and then selects a nominee for recommendation to the Board by majority vote. To date, the Nominating and Corporate Governance Committee has not paid a fee to any third party to assist in the process of identifying or evaluating director candidates.

Stockholder Nominations

The Nominating and Corporate Governance Committee will consider director candidates recommended by stockholders. The Nominating and Corporate Governance Committee does not intend to alter the manner in which it evaluates candidates, including the minimum criteria set forth above, based on whether a candidate was recommended by a stockholder or not. Stockholders who wish to recommend individuals for consideration by the Nominating and Corporate Governance Committee to become nominees for election to the Board of Directors must do so by deliveringCompany. Although at least 120 days prior to the anniversary date of the mailing of MannKind’s proxy statement for its last annual meeting of stockholders a written recommendation to the Nominating and Corporate Governance Committee, c/o MannKind Corporation, 25134 Rye Canyon Loop, Suite 300, Valencia, California 91355, Attn: Corporate Secretary. Each submission must set forth:

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Each submission must be accompanied by the written consent of the proposed candidate to be named as a nominee and to serve as a director if elected. To date, the Nominating and Corporate Governance Committee has not received a timely nomination of a candidate for election as a director at any annual meeting from a stockholder or group of stockholders holding more than 5% of our voting stock.

MEETINGSOFTHE BOARDOF DIRECTORS

The Board of Directors met eleven times during the last fiscal year. Each director attended 75% or more of the aggregate number of the meetings of the Board and of the committees on which he served, held during the period for which he was a director or committee member.

EXECUTIVE SESSIONS

As required under applicable Nasdaq listing standards, our independent directors meet in regularly scheduled executive sessions at which only independent directors are present.

STOCKHOLDER COMMUNICATIONSWITHTHE BOARDOF DIRECTORS

The Company’s Board of Directors has adopted a formal process by which stockholders may communicate with the Board or any of its directors. Stockholders who wish to communicate with the Board or an individual director may send a written communication to the Board or such director c/o MannKind Corporation, 25134 Rye Canyon Loop, Suite 300, Valencia, California 91355, Attn: Corporate Secretary. Communications also may be sent by e-mail to the following address: board@mannkindcorp.com. Each communication must set forth the name and address of the MannKind stockholder on whose behalf the communication is sent. Each communication will be screened by MannKind’s Corporate Secretary to determine whether it is appropriate for presentation to the Board of Directors or such director. Examples of inappropriate communications include junk mail, mass mailings, product complaints, product inquiries, new product suggestions, resumes, job inquiries, surveys, business solicitations and advertisements, as well as unduly hostile, threatening, illegal, unsuitable, frivolous, patently offensive or otherwise inappropriate material. Communications determined by the Corporate Secretary to be appropriate for presentation to the Board of Directors or such director will be submitted to the Board of Directors or such director on a periodic basis.

The screening procedures have been approved by a majority of the independent directors of the Board. All communications directed to the Audit Committee in accordance with the Company’s Code of Business Conduct and Ethics that relate to questionable accounting or auditing matters involving the Company will be promptly and directly forwarded to the Audit Committee.

CODEOF BUSINESS CONDUCTAND ETHICS

We have adopted a Code of Business Conduct and Ethics Policy that applies to our directors and employees (including our principal executive officer, principal financial officer, principal accounting officer and controller), and have posted the text of the policy on our website (www.mannkindcorp.com) in connection with “Investors” materials. In addition, we intend to promptly disclose on our website (i) the nature of any amendment to the policy that applies to our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions and (ii) the nature of any waiver, including an implicit waiver, from a provision of the policy that is granted to one of these specified individuals, the name of such person who is granted the waiver and the date of the waiver.

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COMPENSATION COMMITTEE INTERLOCKSAND INSIDER PARTICIPATION

During the fiscal year ended December 31, 2016, Mr. Kresa and Drs. Friedman and Shannon served on our Compensation Committee. None of Mr. Kresa or Drs. Friedman or Shannon has ever been one of our officers or employees. During 2016, none of our executive officers served as a member of the Board of Directors or Compensation Committee of any other entity that had one or more executive officers who served on our Board of Directors or Compensation Committee.

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PROPOSAL 2

ADVISORY VOTE ON EXECUTIVE COMPENSATION

The Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (the “Dodd-Frank Act”) and Section 14A of the Exchange Act enables the Company’s stockholders to vote to approve, on an advisory or non-binding basis, the compensation of the Company’s named executive officers as described in the “Compensation Discussion and Analysis” section of this proxy statement (commonly referred to as a “say on pay” proposal). This vote is not intended to address any specific item of compensation, but rather the overall compensation of our named executive officers and the philosophy, policies and practices described in this proxy statement.

The compensation of our named executive officers is disclosed in the Compensation Discussion and Analysis, the compensation tables, and the related narrative disclosure contained in this proxy statement. As discussed in those disclosures, the Company believes that its compensation policies and decisions are appropriately designed to attract and retain the individuals needed to support the Company’s business strategy and to compete effectively with pharmaceutical and biotechnology companies while aligning with the long-term interests of the Company’s stockholders

Applying these philosophies,present the Board of Directors has set specific compensation goals designednot approved any plans or proposals to helpissue any of the Company achieveadditional shares of our short and long-term business and performance goals. Our executive compensation program emphasizes pay-for-performance. The compensation packagecommon stock that would become authorized for our executive officers includes both cash and equity incentive plans that align our executives’ compensation with our short-term and long-term performance goals and objectives.

Theissuance if this proposal is approved, the Board of Directors believes thatdesires to have the base salariesshares available to provide additional flexibility to use our common stock for financing and business purposes in the future. Adoption of the proposed amendment and issuance of the common stock would not affect the rights of the holders of currently outstanding common stock of the Company, except for, with respect to the issuance of additional shares, effects incidental to increasing the number of shares of our executivecommon stock outstanding, such as dilution of the earnings per share, if any, and voting rights of current holders of our common stock. If the amendment is adopted, it will become effective upon filing of a Certificate of Amendment of the Company’s Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware.

Unless further stockholder approval is required for a proposed issuance of additional shares by the rules of The Nasdaq Stock Market or other applicable laws or regulations, the additional shares may be used for various purposes without further stockholder approval. These purposes may include: raising capital; providing equity incentives to employees, officers and directors; establishing strategic relationships with other companies; expanding business or product lines through the acquisition of other businesses or products; and other purposes.

The additional shares of common stock that would become available for issuance if the proposal is adopted could also be used by the Company to oppose a hostile takeover attempt or to delay or prevent changes in control or management of the Company. For example, without further stockholder approval, the Board could strategically sell shares of common stock in a private transaction to purchasers who would oppose a takeover or favor the current Board. Although this proposal to increase the authorized common stock has been prompted by business and financial considerations and not by the threat of any hostile takeover attempt (nor is the Board currently aware of any such attempts directed at the Company), stockholders should be set at approximatelyaware that approval of the median base salary levels of executive officers in our competitive market. The annual cash incentive awards under our bonus plan are intended to compensate our executive officers for achieving our annual goals at the corporate level. The goals forproposal could facilitate future efforts by the Company are established so that target attainmentto deter or prevent changes in control of the Company, including transactions in which the stockholders might otherwise receive a premium for their shares over then current market prices.

If this proposal is not assured. approved by our stockholders, our financing alternatives will likely be limited by the lack of sufficient unissued and unreserved authorized shares of common stock, and stockholder value may be harmed by this limitation. In addition, our future success depends upon our ability to attract, retain and motivate highly-skilled scientific, commercial and managerial employees, and if this proposal is not approved by our stockholders, the lack of sufficient unissued and unreserved authorized shares of common stock to provide future equity incentive opportunities as the Board or the Compensation Committee thereof deems appropriate could adversely impact our ability to achieve these goals. In short, if our stockholders do not approve this proposal, we may not be able to access the capital markets, complete corporate collaborations, partnerships or other strategic transactions, attract, retain and motivate employees, and pursue other business opportunities integral to our growth and success.

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Vote Required

The attainmentaffirmative vote of payment for performance at or above target levels requires significant effortthe holders of a majority of the outstanding shares of our common stock on the part of our named executive officers. Our named executive officers’ target annual cash incentive awards are expressed as a percentage of base salary and reflects what we believe are market competitive levels.

Long-term equity incentives are intendedrecord date will be required to reward executives for growth in stockholder value. In 2016, our long-term equity incentive awards to our named executive officers reflectedapprove the grant guidelines we adopted in 2007, and are based on our determination of appropriate and competitive annual award values. The guidelines for executive officers seek to deliver approximately 75%amendment of the award valueCompany’s Amended and Restated Certificate of Incorporation to effect the authorized shares increase. As a result, abstentions and brokernon-votes, if any, will have the same effect as “against” votes.

THE BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS

A VOTE “FOR” THIS PROPOSAL.

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PROPOSAL 2

AUTHORIZATION TO ADJOURN THE SPECIAL MEETING

General

If the Special Meeting is convened and a quorum is present, but there are not sufficient votes to approve Proposal 1, our proxy holders may move to adjourn the Special Meeting at that time in stock options and 25% oforder to enable the award value in restricted stock units. We believeBoard to solicit additional proxies.

In this mix of equity aligns with the interests of stockholders and encourages both stock price growth and retention.

We have limited perquisite benefits (e.g. automobile allowances) for certain of our named executive officers andproposal, we currently do not provide any deferred compensation programs or supplemental pensions to any of our named executive officers.

We believe that our pay practices are reasonable and in the best interests of our Company and our stockholders. To that end, we do not use tax gross-ups, guaranteed bonuses, “single-trigger” benefits payable upon a change in control without a corresponding separation from service, or similar pay practices.

At the 2011 Annual Meeting of Stockholders, our stockholders indicated their preference that the Company solicit a non-binding advisory vote on the compensation of the named executive officers every year. The Board has adopted a policy that is consistent with that preference. In accordance with that policy, this year, we are again asking our stockholders to supportauthorize the compensationholder of the Company’s named executive officers as described in thisany proxy statementsolicited by casting a non-binding advisory vote “FOR” the following resolution:

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“RESOLVED, that the Company’s stockholders approve, on an advisory basis, the compensation of the named executive officers, as disclosed in the Company’s Proxy Statement for the 2017 Annual Meeting of Stockholders pursuant to the compensation disclosure rules of the Securities and Exchange Commission, including the Compensation Discussion and Analysis, the 2016 Summary Compensation Table and the other related tables and disclosure.”

While this advisory vote on executive compensation is non-binding, the Board of Directors to vote in favor of granting discretionary authority to the proxy holders, and each of them individually, to adjourn the Compensation Committee, which is responsible for designingSpecial Meeting to another time and administeringplace, if necessary, to solicit additional proxies in the Company’s executive compensation program, will reviewevent there are not sufficient votes to approve Proposal 1. If our stockholders approve this proposal, we could adjourn the voting resultsSpecial Meeting and consider the outcomeany adjourned session of the Special Meeting and use the additional time to solicit additional proxies, including the solicitation of proxies from our stockholders that have previously voted. Among other things, approval of this proposal could mean that, even if we had received proxies representing a sufficient number of votes to defeat Proposal 1, we could adjourn the Special Meeting without a vote when making future compensation decisions for named executive officers.on such proposal and seek to convince our stockholders to change their votes in favor of such proposal.

UnlessIf it is necessary to adjourn the Board decidesSpecial Meeting, no notice of the adjourned meeting is required to modify its policy regarding the frequency of soliciting say-on-pay votes, the next scheduled say-on-pay vote will be given to our stockholders, other than an announcement at the 2018 AnnualSpecial Meeting of Stockholders.the time and place to which the Special Meeting is adjourned, so long as the meeting is adjourned for 30 days or less and no new record date is fixed for the adjourned meeting. At the adjourned meeting, we may transact any business which might have been transacted at the original meeting.

REQUIRED VOTEAND BOARDOF DIRECTORS RECOMMENDATIONVote Required

Approval of Proposal 2this proposal requires the affirmative vote of a majority of the shares of our common stock present or represented by proxy at the Special Meeting and entitled to vote at the Annual Meeting. Abstentions will be counted toward the tabulation of votes cast on the proposal andsuch matter. Accordingly, if you “Abstain” from voting, it will have the same effect as an “Against” votes.vote. Brokernon-votes, are counted towards a quorum, but if any, will have no effect on the outcome of the vote.

The Board of Directors recommends that you vote in favor of the compensation of the Company’s named executive officers as described in this proxy statement, including the disclosures under “Compensation Discussion and Analysis,” the compensation tables and the narrative discussion following the compensation tables.

THE BOARDOF DIRECTORS RECOMMENDS

AVOTEFOR PROPOSAL 2

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PROPOSAL 3

ADVISORY INDICATION ON THE PREFERRED FREQUENCY OF STOCKHOLDER ADVISORY

VOTE ON EXECUTIVE COMPENSATION

The Dodd-Frank Act also enables the Company’s stockholders to indicate their preference regarding how frequently the Company should solicit a non-binding advisory vote on the compensation of our named executive officers as disclosed in the Compensation Discussion and Analysis, the compensation tables, and the related narrative disclosure. Currently, consistent with the preference expressed by the stockholders at the Company’s 2011 Annual Meeting of Stockholders, the policy of the Board is to solicit such vote every year. In accordance with the Dodd-Frank Act, we are again asking stockholders to indicate whether they would prefer an advisory vote once every one, two or three years. Alternatively, stockholders may abstain from casting a vote. For the reasons described below, we recommend that our stockholders select a frequency of one year, or an annual vote.

In formulating its recommendation, the Board of Directors considered several factors in determining the appropriate frequency of advisory votes on executive compensation. On the one hand, the Board of Directors recognizes the importance of receiving regular input from our stockholders on important issues, such as our compensation policies and procedures. The Board of Directors also believes that a well-structured compensation program should include plans that drive the creation of stockholder value over the long term and do not simply focus on short-term gains. Because of that, the Board of Directors believes that an annual advisory vote will be more limited in value than a vote which reflects the long-term executive compensation philosophy of the Compensation Committee and the long-term results of its actions. Moreover, many elements of compensation are structured over a multi-year period, disclosure is made to cover several years, and some proxy advisory firms review total stockholder returns over multi-year periods. Also, equity awards to management are granted to compensate management over at least a three-year period. On the other hand, the Board of Directors recognizes that even if the effectiveness of these plans cannot be adequately evaluated on an annual basis, many stockholders may want to express a preference in a single year based on a multi-year review. An annual say-on-pay vote may represent the most effective means for some of our stockholders to express meaningful input on executive compensation. Because of that, the Board of Directors determined that an annual say-on-pay vote would best express its commitment to take steps to align the compensation of its executives with the interests of the Company’s stockholders. The Board of Directors’ determination was further based on the premise that this recommendation could be modified in future years if it becomes apparent that an annual say-on-pay vote is not meaningful, is burdensome or is more frequent than recommended by best corporate governance practices. Based on these factors, the Board of Directors determined to recommend that future say-on-pay votes occur each year until the next vote on the frequency of advisory votes on the compensation of our named executive officers.

Stockholders are provided with the opportunity to choose among four options (holding the vote every one, two or three years, or abstaining) and, therefore, stockholders will not be voting to approve or disapprove the recommendation of the Board of Directors. The option among those choices that obtains a majority of votes cast by the shares present or represented by proxy and entitled to vote at the Annual Meeting will be deemed to be the frequency adopted for advisory purposes by our stockholders in accordance with our Amended and Restated Bylaws; however, in the event that no frequency receives a majority, we will consider whichever frequency receives a plurality of the votes to be the frequency preferred by our stockholders.

The Board and the Compensation Committee value the opinions of our stockholders in this matter, and the Board of Directors intends to hold say-on-pay votes in the future in accordance with the alternative that receives the most stockholder support.

THE BOARDOF DIRECTORSRECOMMENDS

AVOTEINFAVOROF “ONE YEAR”ON PROPOSAL 3.

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PROPOSAL 4

RATIFICATION OF SELECTION OF DELOITTE & TOUCHE LLP AS INDEPENDENT

REGISTERED PUBLIC ACCOUNTING FIRM

The Audit Committee of the Board of Directors has selected Deloitte & Touche LLP (“Deloitte”), as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2017 and has directed management to submit the selection of Deloitte for ratification by the stockholders at the Annual Meeting.

Deloitte has audited the Company’s financial statements since the fiscal year ended December 31, 2000. Representatives of Deloitte are expected to be present at the Annual Meeting. They will have an opportunity to make a statement if they so desire and will be available to respond to appropriate questions.

Stockholder ratification of the selection of Deloitte as our independent registered public accounting firm is not required by our Amended and Restated Bylaws or otherwise. The Board of Directors is seeking such ratification as a matter of good corporate practice. If the stockholders fail to ratify the selection of Deloitte as our independent registered public accounting firm, the Audit Committee of the Board of Directors will consider whether to retain that firm for the fiscal year ending December 31, 2017.

Approval of Proposal 4 requires the affirmative vote of a majority of the shares present or represented by proxy and entitled to vote at the Annual Meeting. Abstentions will be counted toward the tabulation of votes cast on the proposal and will have the same effect as “Against” votes. Broker non-votes are counted towards a quorum, but will have no effect on the outcome of the vote.

THE BOARDTHE BOARD OF DIRECTORS RECOMMENDS DIRECTORS UNANIMOUSLY RECOMMENDS

A VOTEFOR PROPOSAL 4

PRINCIPAL ACCOUNTING FEESAND SERVICES

The following table represents aggregate fees billed to the Company for the fiscal years ended December 31, 2016 and 2015 by Deloitte and its subsidiaries, the affiliates of Deloitte & Touche LLP, Deloitte Tohmatsu Limited and its member firm. All entities which collectively represent the Company’s principal accounting firm.

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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table sets forth certain information regarding the ownership of the Company’s common stock as of                 March 17,, 2017 by: (i) each person, entity or group known to the Company to be the beneficial owner of more than 5% of the Company’s common stock; (ii) each director and nominee for director;of our directors; (iii) each of the executive officers named in the Summary Compensation Table (other than Mr. Mann), who we refer to as theour named executive officers; and (iv) all current executive officers and directors of the Company as a group. Unless otherwise indicated in the footnotes to the table below and subject to community property laws where applicable, we believe that each of the stockholders named in the table has sole voting and investment power with respect to the shares indicated as beneficially owned.

Applicable percentages are based on              95,776,246 shares outstanding on                 March 17,, 2017, adjusted as required by rules promulgated by the SEC. These rules generally attribute beneficial ownership of securities to persons who possess sole or shared voting power or investment power with respect to those securities. In addition, the rules include shares of common stock issuable pursuant to the exercise of stock options or warrants that are either immediately exercisable or exercisable on or before                 May 16,, 2017, which is 60 days after                 March 17,, 2017. These shares are deemed to be outstanding and beneficially owned by the person holding those options or warrants for the purpose of computing the percentage ownership of that person, but they are not treated as outstanding for the purpose of computing the percentage ownership of any other person. Certain of the options in this table are exercisable at any time but, if exercised, are subject to a lapsing right of repurchase until the options are fully

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vested. Unless otherwise indicated, the address for each person or entity listed in the table is c/o MannKind Corporation, 25134 Rye Canyon Loop,30930 Russell Ranch Road, Suite 300, Valencia,301, Westlake Village, CA 91355.91362.

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Appendix A

CERTIFICATE OF AMENDMENT OF

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

MANNKIND CORPORATION

MANNKIND CORPORATION, a corporation organized and existing under and by virtue of the General Corporation Law of the State of Delaware (the “Corporation”), does hereby certify:

FIRST: The original name of the Corporation was Pharmaceutical Discovery Corporation. The date on which the Corporation’s original Certificate of Incorporation was filed with the Secretary of State of the State of Delaware is February 14, 1991.

SECOND: The Board of Directors of the Corporation (the “Board”), acting in accordance with the provisions of Sections 141 and 242 of the General Corporation Law of the State of Delaware (the “DGCL”), adopted resolutions amending its Amended and Restated Certificate of Incorporation, as amended (the “Restated Certificate”), as follows:

The first paragraph of Paragraph A of Article IV of the Restated Certificate is hereby amended and restated to read in its entirety as follows:

“A.    This Corporation is authorized to issue two classes of stock to be designated, respectively, “Common Stock” and “Preferred Stock.” The total number of shares which the Corporation is authorized to issue is two hundred ninety million (290,000,000) shares. Two hundred eighty million (280,000,000) shares shall be Common Stock, each having a par value of one cent ($.01). Ten million (10,000,000) shares shall be Preferred Stock, each having a par value of one cent ($.01).”

THIRD: The foregoing amendment was submitted to the stockholders of the Corporation for their approval at a special meeting of stockholders which was duly called and held, upon notice in accordance with Section 222 of the DGCL, at which meeting the necessary number of shares as required by statute were voted in favor of the amendment. Accordingly, said amendment was duly adopted in accordance with the provisions of Section 242 of the DGCL.

FOURTH: This Certificate of Amendment shall become effective upon filing with the Secretary of State of the State of Delaware.

IN WITNESS WHEREOF, MannKind Corporation has caused this Certificate of Amendment to be signed by its Corporate Vice President, General Counsel and Secretary on            , 2017.