Appian : 2024 Proxy Statement

APPIAN CORPORATION

7950 Jones Branch Drive

McLean, Virginia 22102

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held on June 6, 2024

Dear Stockholder:

You are cordially invited to attend the 2024 Annual Meeting of Stockholders, or Annual Meeting, of APPIAN CORPORATION, a Delaware corporation (the "Company"). The Annual Meeting will be held on Thursday, June 6, 2024, at 11:00 a.m. Eastern Time. The Annual Meeting will be a virtual stockholder meeting through which you can listen to the meeting, submit questions, and vote online. You will not be able to attend the meeting in person. The Annual Meeting can be accessed by visiting www.virtualshareholdermeeting.com/APPN2024 and entering your 16- digit control number (included on the Notice Regarding the Availability of Proxy Materials mailed to you). The purpose of the Annual Meeting will be the following:

1. To elect the seven (7) nominees for director named herein to serve until the 2025 Annual Meeting of Stockholders and until their successors have been duly elected and qualified.
2. To ratify the selection by the Audit Committee of the Board of Directors of BDO USA, P.C. as the independent registered public accounting firm of the Company for its fiscal year ending December 31, 2024.
3. To approve, on an advisory basis, the compensation of the Company's named executive officers as disclosed in the Proxy Statement.
4. To conduct any other business properly brought before the Annual Meeting.

These items of business are more fully described in the Proxy Statement accompanying this Notice.

The record date for the Annual Meeting is April 8, 2024. Only stockholders of record at the close of business on that date may vote at the Annual Meeting or any adjournment thereof. For the ten days prior to the Annual Meeting, a list of stockholders entitled to vote at the Annual Meeting will be available for examination by any stockholder of record for purposes germane to the Annual Meeting at our corporate headquarters during regular business hours. In addition, during the Annual Meeting, that list of stockholders will be available for examination by any stockholder of record at www.virtualshareholdermeeting.com/APPN2024.

By Order of the Board of Directors,

Christopher Winters

General Counsel and Secretary

McLean, Virginia

April 25, 2024

We are primarily providing access to our proxy materials over the Internet pursuant to the Securities and Exchange Commission's notice and access rules. On or about April 25, 2024, we expect to mail to our stockholders of record as of April 8, 2024, a Notice of Internet Availability of Proxy Materials that will indicate how to access our 2024 Proxy Statement and 2023 Annual Report on the Internet and will include instructions on how you can receive a paper copy of the Annual Meeting materials, including the notice of annual meeting, proxy statement, and proxy card.

Whether or not you expect to attend the virtual Annual Meeting, please submit voting instructions for your shares promptly using the directions on your Notice, or, if you elected to receive printed proxy materials by mail, your proxy card, to vote by one of the following methods: (1) over the Internet before the Annual Meeting at www.proxyvote.com and during the Annual Meeting at www.virtualshareholdermeeting.com/APPN2024, (2) by telephone by calling the toll-free number 1-800-690-6903, or (3) if you elected to receive printed proxy materials by mail, by marking, dating, and signing your proxy card and returning it in the accompanying postage-paid envelope. Even if you have voted by proxy, you may still vote online if you attend the virtual Annual Meeting. Please note, however, that if your shares are held of record by a broker, bank, or other nominee and you wish to vote online at the Annual Meeting, you must obtain a proxy issued in your name from that record holder.

TABLE OF CONTENTS

Questions and Answers About These Proxy Materials and Voting	1
Proposal No. 1 - Election of Directors	7
Information Regarding the Board of Directors and Corporate Governance	9
Independence of the Board of Directors	9
Board Leadership Structure	9
Role of the Board in Risk Oversight	10
Meetings of the Board of Directors	10
Information Regarding Committees of the Board of Directors	10
Board Diversity Matrix	14
Stockholder Communications with the Board of Directors	14
Code of Ethics	15
Insider Trading Policy	15
Proposal No. 2 - Ratification of Selection of Independent Registered Public Accounting Firm	16
Proposal No. 3 - Advisory Vote on Named Executive Officer Compensation	17
Executive Officers	18
Security Ownership of Certain Beneficial Owners and Management	19
Executive and Director Compensation	21
Compensation Discussion and Analysis	21
Summary Compensation Table	27
Grants of Plan-Based Awards in 2023	28
Outstanding Equity Awards at December 31, 2023	29
Option Exercises and Stock Vested in 2023	30
Employment Agreements	30
Equity Plan Terms	31
Summary of Estimated Amounts Payable Upon a Termination or Change in Control	31
CEO Pay Ratio	32
Pay Versus Performance	33
Director Compensation	36
Securities Authorized for Issuance Under Equity Compensation Plans	38
Limitations on Liability and Indemnification Matters	38
Transactions with Related Persons	39
Related Person Transactions Policy and Procedures	39
Certain Related Person Transactions	39
Householding of Proxy Materials	40
Other Matters	40
Appendix A - Non-GAAP Reconciliation	41

APPIAN CORPORATION

7950 JONES BRANCH DRIVE, MCLEAN, VIRGINIA 22102

PROXY STATEMENT

FOR THE 2024 ANNUAL MEETING OF STOCKHOLDERS

To Be Held on June 6, 2024

QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS AND VOTING

Why did I receive a notice regarding the availability of proxy materials on the Internet?

Pursuant to rules adopted by the Securities and Exchange Commission (the "SEC"), we have elected to provide 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 (the "Board") of Appian Corporation (sometimes referred to as the "Company," "Appian," "we," "us," or "our") is soliciting your proxy to vote at the 2024 Annual Meeting of Stockholders (the "Annual Meeting"), including at any adjournments or postponements of the Annual Meeting. All stockholders will have the ability to access the proxy materials on the website referred 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.

We intend to mail the Notice on or about April 25, 2024 to all stockholders of record entitled to vote at the Annual Meeting.

How do I attend the Annual Meeting?

The Annual Meeting will be held on Thursday, June 6, 2024, at 11:00 a.m. Eastern Time. The Annual Meeting will be a virtual stockholder meeting through which you can listen to the meeting, submit questions, and vote online. The Annual Meeting can be accessed by visiting www.virtualshareholdermeeting.com/APPN2024 and entering your 16-digit control number which is included in the Notice that will be mailed to you. We recommend you log in a few minutes before the Annual Meeting on June 6, 2024 to ensure you are logged in when the meeting starts. Online check-in will begin at 10:55 a.m. Eastern Time.

We have decided to hold a virtual meeting because it improves stockholder access, encourages greater global participation, lowers costs compared to an in-person event, and aligns with our broader sustainability goals. Stockholders attending the virtual meeting will be afforded the same rights and opportunities to participate as they would at an in-person meeting.

Information on how to vote online during the Annual Meeting is discussed below.

Can I ask questions at the Annual Meeting?

Only stockholders of record as of the record date for the Annual Meeting and their proxy holders may submit questions or comments.

If you would like to submit a question, you may do so by joining the virtual Annual Meeting at www.virtualshareholdermeeting.com/APPN2024 and typing your question in the box in the Annual Meeting portal.

To help ensure we have a productive and efficient meeting and in fairness to all stockholders in attendance, you will also find posted our rules of conduct for the Annual Meeting when you log in prior to its start. In accordance with the rules of conduct, we ask you limit your remarks to one brief question or comment that is relevant to the Annual Meeting or our business and that remarks are respectful of your fellow stockholders and meeting participants. Questions may be grouped by topic by our management with a representative question read aloud and answered. In addition, questions may be ruled as out of order if they are, among other things, irrelevant to our business, related to pending or threatened litigation, disorderly, repetitious of statements already made, or in furtherance of the speaker's own personal, political, or business interests. Questions will be addressed in the Q&A portion of the Annual Meeting.

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What if I need technical assistance accessing or participating in the virtual Annual Meeting?

If you encounter any difficulties accessing the virtual Annual Meeting during the check-in or meeting time, please call the technical support number that will be posted on the Virtual Stockholder Meeting log in page. Technical support will be available starting at 10:30 a.m. Eastern Time on June 6, 2024.

Who can vote at the Annual Meeting?

Only stockholders of record of our Class A common stock and Class B common stock at the close of business on April 8, 2024, will be entitled to vote at the Annual Meeting. On this record date, there were 41,039,443 shares of Class A common stock outstanding and entitled to vote and 31,196,796 shares of Class B common stock outstanding and entitled to vote. Holders of our Class A common stock are entitled to one vote for each share held as of the above record date. Holders of our Class B common stock are entitled to ten votes for each share held as of the above record date. Holders of our Class A and Class B common stock will vote together as a single class on all matters described in this proxy statement.

A quorum of stockholders is necessary to hold a valid meeting. A quorum will be present if stockholders holding at least a majority of the voting power of the outstanding shares of our Class A common stock and Class B common stock (voting together as a single class) entitled to vote are present at the meeting or represented by proxy. 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 at the Annual Meeting. Abstentions and broker non-votes will be counted towards the quorum requirement. If there is no quorum, the chairperson of the meeting or the holders of a majority of the voting power of shares present at the Annual Meeting or represented by proxy may adjourn the Annual Meeting to another date.

Stockholder of Record: Shares Registered in Your Name

If on April 8, 2024 your shares were registered directly in your name with our transfer agent, Computershare Trust Company, N.A., then you are a stockholder of record. As a stockholder of record, you may vote online at the Annual Meeting or vote by proxy. Whether or not you plan to participate in the Annual Meeting, we urge you to vote by proxy over the Internet, by telephone, or by mail as instructed below to ensure your vote is counted.

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

If on April 8, 2024 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 the Notice is being forwarded to you by that organization. The organization holding your shares is considered to be the stockholder of record for purposes of voting at the Annual Meeting. As a beneficial owner, you have the right to direct your broker or other agent regarding how to vote the shares in your account. You are also invited to attend the Annual Meeting. However, since you are not the stockholder of record, you may not vote your shares at the Annual Meeting unless you request and obtain a valid proxy from your broker or other agent.

Will a list of stockholders entitled to vote at the Annual Meeting be available?

For the ten days prior to the Annual Meeting, a list of stockholders entitled to vote at the Annual Meeting will be available for examination by any stockholder of record for purposes germane to the Annual Meeting at our corporate headquarters during regular business hours. To access the list of record stockholders beginning ten days prior to the Annual Meeting and until the meeting, stockholders can schedule an appointment by contacting the Corporate Secretary at [phone]. In addition, during the Annual Meeting, that list of stockholders will be available for examination by any stockholder of record at www.virtualshareholdermeeting.com/APPN2024.

What am I voting on?

There are three matters scheduled for a vote:

• Proposal No. 1: Election of seven directors;

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• Proposal No. 2: Ratification of the selection by the Audit Committee of the Board of Directors of BDO USA, P.C. ("BDO") as independent registered public accounting firm of the Company for its fiscal year ending December 31, 2024; and
• Proposal No. 3: Advisory approval of the compensation of our named executive officers, as disclosed in this Proxy Statement in accordance with SEC rules.

What if another matter is properly brought before the meeting?

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

How do I vote?

You may either vote "For" any or all of the proposed nominees to the Board or you may "Withhold" your vote for any nominee you specify. Proxies cannot be voted for a greater number of persons than the nominees named in this Proxy Statement. For each of the other matters to be voted on, you may vote "For" or "Against" or abstain from voting.

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record, you may vote at the Annual Meeting or vote by proxy. Whether or not you plan to participate in the Annual Meeting, we urge you to vote by proxy over the Internet, by telephone, or by mail as instructed below to ensure your vote is counted. You may still attend the Annual Meeting via the Internet and vote during the Annual Meeting even if you have already voted by proxy.

Vote by Internet

Before the Annual Meeting

To vote through the Internet before the Annual Meeting, go to www.proxyvote.com to complete an electronic proxy card. Have your notice in hand when you access the website and then follow the instructions. If you choose to vote through the Internet before the Annual Meeting, your vote must be received by 11:59 p.m. Eastern Time on June 5, 2024, the day before the Annual Meeting, to be counted.

During the Annual Meeting

You may attend the Annual Meeting via the Internet and vote during the Annual Meeting. The Annual Meeting can be accessed by visiting www.virtualshareholdermeeting.com/APPN2024 and entering your 16-digit control number which is included in the notice that will be mailed to you. Have your notice in hand when you access the website and then follow the instructions.

Vote by Telephone

To vote over the telephone, dial toll-free1-800-690-6903 using a touch-tone phone and follow the recorded instructions. You will be asked to provide the company number and control number from the Notice. Your telephone vote must be received by 11:59 p.m. Eastern Time on June 5, 2024, the day before the Annual Meeting, to be counted. Have your notice in hand when you call.

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Vote by Mail

To vote using the proxy card, simply complete, sign, and date the proxy card that may be delivered and return it promptly in the envelope provided. If you return your signed proxy card to us before the Annual Meeting, we will vote your shares as you direct.

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 nominee, you should have received a Notice containing voting instructions from that organization rather than from Appian. Simply follow the voting instructions in the Notice to ensure your vote is counted. To vote at the Annual Meeting, you must obtain a valid proxy from the broker, bank, or other nominee that holds your shares. Follow the instructions from that organization included with these proxy materials or contact that organization to request a proxy form.

Internet proxy voting may be provided 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 you must bear any costs associated with your Internet access such as usage charges from Internet access providers and telephone companies.

How many votes do I have?

On each matter to be voted upon, you have one vote for each share of Class A common stock you own as of April 8, 2024 and ten votes for each share of Class B common stock you own as of April 8, 2024.

What happens if I do not vote?

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record and do not vote by completing your proxy card, by telephone, or through the Internet either before or during the Annual Meeting, your shares will not be voted.

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

If your shares are held by your broker or bank as your nominee (that is, in "street name") and you do not instruct your broker, bank, or other nominee how to vote your shares, under stock exchange rules your broker or nominee will only have discretion to vote your shares on "routine" matters. Where a proposal is not "routine," a broker or nominee who has not received instructions from its clients does not have discretion to vote its clients' uninstructed shares on that proposal. At our Annual Meeting, only the ratification of the appointment of BDO as independent registered public accounting firm of the Company for the year ending December 31, 2024 (Proposal No. 2) is considered a routine matter. Accordingly, your broker or nominee may not vote your shares on Proposal Nos. 1 and 3 without your instructions but may vote your shares on Proposal No. 2 even in the absence of your instruction.

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

If you return a signed and dated proxy card or otherwise vote without marking voting selections, your shares will be voted, as applicable, "For" the election of the nominees for director (Proposal No. 1), "For" the ratification of the appointment of BDO as independent registered public accounting firm of the Company for the year ending December 31, 2024 (Proposal No. 2), and "For" the advisory approval of named executive officer compensation (Proposal No. 3). If any other matter is properly presented at the meeting, your proxyholder (one of the individuals named on your proxy card) will vote your shares using his or her best judgment.

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 may also reimburse brokerage firms, banks, and other agents for the cost of forwarding proxy materials to beneficial owners.

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

If you receive more than one Notice, your shares may be registered in more than one name or in different accounts. Please follow the voting instructions on the Notices to ensure all of your shares are voted.

Can I change my vote after submitting my proxy?

Stockholder of Record: Shares Registered in Your Name

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

• You may submit another properly completed proxy card with a later date.
• You may grant a subsequent proxy by telephone or through the Internet.
• You may send a written notice that you are revoking your proxy to us at Appian Corporation, 7950 Jones Branch Drive, McLean, Virginia 22102, Attention: Secretary.
• You may attend the Annual Meeting and vote online. Simply attending the Annual Meeting will not, by itself, revoke your proxy.

Your most current proxy card or telephone or Internet proxy is the one that is counted.

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

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.

When are stockholder proposals and director nominations due for the 2025 Annual Meeting of Stockholders?

If you are interested in submitting a proposal for potential inclusion in the proxy statement for our 2025 Annual Meeting of Stockholders, you must follow the procedures outlined in Rule 14a-8 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). To be eligible for inclusion in the proxy statement, we must receive your stockholder proposal at the address noted below no later than December 26, 2024. However, if the 2025 Annual Meeting of Stockholders is held before May 7, 2025 or after July 6, 2025, then we must receive your stockholder proposal at the address noted below a reasonable time before we begin to print and mail our proxy materials for the 2025 Annual Meeting of Stockholders.

If you wish to present a proposal at the 2025 Annual Meeting of Stockholders but do not wish to have the proposal considered for inclusion in our proxy statement and proxy card, you must also give written notice at the address noted below. We must receive this required notice by the close of business on March 8, 2025 but no sooner than the close of business on February 5, 2025. However, if our 2025 Annual Meeting of Stockholders is held before May 7, 2025 or after July 6, 2025, then we must receive the required notice of a proposal or proposed director candidate no earlier than the close of business on the 120th day prior to the 2025 Annual Meeting of Stockholders and no later than the close of business on the later of (1) the 90th day prior to the 2025 Annual Meeting of Stockholders or (2) the tenth day following the date on which public disclosure was made of the date of the 2025 Annual Meeting of Stockholders.

Any proposals for the 2025 Annual Meeting of Stockholders should be sent to our headquarters: Appian

Corporation, 7950 Jones Branch Drive, McLean, Virginia 22102, Attention: Secretary.

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What are "broker non-votes"?

As discussed above, 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 to be "non-routine," the broker or nominee cannot vote the shares. These unvoted shares are counted as "broker non-votes."

How many votes are needed to approve each proposal?

Proposal

1. Election of Directors
2. Ratification of Auditors
3. Advisory Approval of the Compensation of our Named Executive Officers

Vote Required to Approve		Effect of Abstentions		Effect of Broker Non-Votes
Nominees receiving the most "FOR"		Not applicable		No effect
votes.
"FOR" votes from a majority of the		Against		Not applicable, as brokers can
voting power of the shares of our				vote the shares given this is
Class A common stock and Class B				considered a "routine" matter.
common stock (voting together as a
single class) present or represented
by proxy and entitled to vote on the
proposal.
"FOR" votes from a majority of the		Against		No effect
voting power of the shares of our
Class A common stock and Class B
common stock (voting together as a
single class) present or represented
by proxy and entitled to vote on the
proposal.

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

Preliminary voting results will be announced at the Annual Meeting. In addition, final voting results will be published in a Current Report on Form 8-K.

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PROPOSAL NO. 1

ELECTION OF DIRECTORS

Our business affairs are managed under the direction of our Board, which is currently composed of eight members. Mr. Mulligan, who has served as a director since 2008, is not standing for re-election and will depart the Board effective immediately following the Annual Meeting.

The Board of Directors has nominated the following seven individuals to stand for election at the Annual Meeting. Each of the nominees listed below is currently a director of the Company who was previously elected by the stockholders. The Board has found each nominee to be qualified based on his or her qualifications, experience, attributes, skills, and whether he or she meets the applicable independence standards. Each director elected and qualified will hold office from the date of their election by the stockholders until the subsequent annual meeting of stockholders and until their successor is duly elected and has been qualified or until such director's earlier death, resignation, or removal.

Directors are elected by a plurality of the votes of the shares present or represented by proxy at the Annual Meeting and entitled to vote on the election of directors. Accordingly, 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 will be voted for the election of a substitute nominee proposed by Appian. Each person nominated for election has agreed to serve if elected. Our management team has no reason to believe any nominee will be unable to serve.

DIRECTOR 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 recommend that person as a nominee for director, as of the date of this proxy statement.

Our Board of Directors seeks to assemble a Board that, as a whole, possesses the appropriate balance of professional and industry knowledge, financial expertise, and high-level management experience necessary to oversee and direct the Company's business and that is committed to rigorously represent the long-term interests of the Company's stockholders. To that end, the Nominating and Corporate Governance Committee has identified, evaluated, and recommended nominees in the broader context of the Board's overall composition, with the goal of recruiting members who complement and strengthen the skills of other members and who also exhibit personal integrity and ethics, collegiality, sound business judgment, and other qualities the Nominating and Corporate Governance Committee views as critical to effective functioning of the Board, including gender, racial, and ethnic diversity. The brief biographies below include information, as of the date of this proxy statement, regarding the specific and particular experience, qualifications, attributes, or skills of each nominee that led the Nominating and Corporate Governance Committee and our Board of Directors to believe the nominee should serve on the Board. At the recommendation of the Nominating and Corporate Governance Committee, the Board of Directors has nominated the following seven persons to serve as directors for the term beginning at the Annual Meeting:

Name		Age		Position Held with the Company
Matthew Calkins	51		Chief Executive Officer, President, Founder, and Chairman of the Board
Robert C. Kramer	49		General Manager, Founder, and Director
A.G.W. "Jack" Biddle, III	63		Director
Shirley A. Edwards	63		Director
Barbara "Bobbie" Kilberg	79		Director
Mark Lynch	60		Director and Former Chief Financial Officer
William D. McCarthy	58		Director

Matthew Calkins is a Founder of Appian and has served as our Chief Executive Officer, President, and as Chairman of our Board of Directors since August 1999. He also served as a director of MicroStrategy, Inc., a publicly held provider of enterprise software platforms, from November 2004 to April 2014. Mr. Calkins holds a B.A. in Economics

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