The AuditCompensation Committee

Corporate Governance Committee

Stockholder Communications with the Board of Directors

Code of Ethics

Corporate Governance Guidelines

Policy Against Hedging Transactions

Certain Relationships and Related Transactions

Director Compensation

EXECUTIVE OFFICERS

EXECUTIVE COMPENSATION

PROPOSAL NO. 2: ADVISORY VOTE ON EXECUTIVE COMPENSATION

Compensation Discussion and Analysis

Executive Summary

Executive Compensation-Setting Process

Elements of Compensation and 2019 Determinations

Compensation Committee has prepared the following report on its activities with respectReport

Executive Compensation Tables

Summary Compensation Table

Grants of Plan-Based Awards

Narrative Disclosure to our audited financial statements for the year ended December 31, 2015.Summary Compensation Table and Grants of Plan-Based Awards Table

Outstanding Equity Awards at Fiscal Year End

Option Exercises and Stock Vested

Severance and Change of Control Arrangements

Potential Payments Upon Termination or Change of Control

Risk Analysis of Our management is responsible for the preparation, presentationCompensation Plans

CEO Pay Ratio

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QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS AND VOTING

Why am I receiving these materials?

        The Company has sent you this proxy statement and the enclosed proxy card because the Board of Directors (the "Board") of Omnicell, Inc. is soliciting your proxy to vote at the 2020 Annual Meeting of Stockholders (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. Instead, you may simply complete, sign and return the enclosed proxy card, or follow the instructions below to submit your proxy over the telephone or the Internet.

        The Company intends to mail this proxy statement and accompanying proxy card on or about April 9, 2020 to all stockholders of record entitled to vote at the Annual Meeting.

Who can vote at the Annual Meeting?

        Only stockholders of record at the close of business on March 30, 2020 will be entitled to vote at the Annual Meeting. On the record date, there were 42,601,447 shares of common stock outstanding and entitled to vote.

Stockholder of Record: Shares Registered in Your Name

        If on March 30, 2020 your shares were registered directly in your name with Omnicell's transfer agent, Computershare Trust Company, N.A., then you are a stockholder of record. As a stockholder of record, you may vote in person at the meeting or vote by proxy. Whether or not you plan to attend the meeting, we urge you to fill out and return the enclosed proxy card or vote by proxy over the telephone or on the Internet as instructed below to ensure your vote is counted.

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

        If on March 30, 2020 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 these 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 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 in person at the meeting unless you request and obtain a valid proxy from your broker or other agent.

Directions to the Annual Meeting

        The Annual Meeting will be held at the Company's headquarters located at 590 E. Middlefield Road, Mountain View, California 94043.

        If you need directions to the meeting, please visithttps://goo.gl/maps/pbCcc.

While we intend to hold our Annual Meeting in person, as part of our precautions regarding the coronavirus or COVID-19, we are planning for the possibility that the Annual Meeting may be held solely by means of remote communication if we determine it is not possible or advisable to hold an in-person meeting. If we take this step, we will announce the decision to do so in advance of our Annual Meeting, and details on how to participate will be posted on our website and filed with the SEC as additional proxy material.

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What am I voting on?

        There are three (3) matters scheduled for a vote:

•

The election of three (3) Class I directors to hold office until the 2023 Annual Meeting of Stockholders;



•

An advisory vote to approve named executive officer compensation; and



•

The ratification of the selection by the Audit Committee of the Board of Deloitte & Touche LLP as the independent registered public accounting firm of the Company for the year ending December 31, 2020.

What if another matter is properly brought before the meeting?

        The Board 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" all the nominees to the Board or you may "Withhold" your vote for any nominee you specify. For each of the other matters to be voted on, you may vote "For" or "Against" or abstain from voting. 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 Annual Meeting, vote by proxy using the enclosed proxy card, vote by proxy over the telephone, or vote by proxy over the Internet. Whether or not you plan to attend the meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the meeting and vote in person even if you have already voted by proxy.

•

To vote in person, come to the Annual Meeting and we will give you a ballot when you arrive.



•

To vote using the proxy card, simply complete, sign and date the enclosed proxy card 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.



•

To vote over the telephone, dial toll-free 1-800-652-VOTE (1-800-652-8683) using a touch-tone phone and follow the recorded instructions. You will be asked to provide the control number from the enclosed proxy card. Your vote must be received by 11:59 p.m. Pacific Time, on May 25, 2020 to be counted.



•

To vote over the Internet, go tohttp://www.investorvote.com/OMCL and follow the steps outlined to complete an electronic proxy card. You will be asked to provide the company number and control number from the enclosed proxy card. Your vote must be received by 11:59 p.m. Pacific Time, on May 25, 2020 to be counted.

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 proxy card and voting instructions with these proxy materials from that organization rather than from Omnicell. Simply complete and mail the proxy card to ensure that your vote is counted. Alternatively, you may vote by telephone or over the Internet as instructed by your broker or bank. To vote in person at the Annual Meeting, you must obtain a valid proxy from

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your broker, bank, or other agent. Follow the instructions from your broker or bank included with these proxy materials, or contact your broker or bank to request a proxy form.

We provide Internet proxy voting to allow you to vote your shares on-line, 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.

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 30, 2020.

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, through the Internet or in person at the Annual Meeting, your shares will not be voted.

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

        If you are a beneficial owner and do not instruct your broker, bank, or other agent how to vote your shares, the question of whether your broker or nominee will still be able to vote your shares depends on whether the New York Stock Exchange ("NYSE") deems the particular proposal to be a "routine" matter. Brokers and nominees can use their discretion to vote "uninstructed" shares with respect to matters that are considered to be "routine," but not with respect to "non-routine" matters. Under the rules and interpretations of the NYSE, "non-routine" matters are matters that may substantially affect the rights or privileges of stockholders, such as mergers, stockholder proposals, elections of directors (even if not contested), executive compensation (including any advisory stockholder votes on executive compensation and on the frequency of stockholder votes on executive compensation), and certain corporate governance proposals, even if management-supported. Accordingly, your broker or nominee may not vote your shares on Proposals 1 or 2 without your instructions, but may vote your shares on Proposal 3 even in the absence of your instructions.

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 without marking any voting selections, your shares will be voted as follows:

•

"For" the election of all three (3) Class I directors;



•

"For" an advisory resolution approving named executive officer compensation; and



•

"For" the ratification of the selection of Deloitte & Touche LLP as the independent registered public accounting firm of the Company for the year ending December 31, 2020.

        If any other matter is properly presented at the meeting, your proxy holder (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 mailed 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

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

What does it mean if I receive more than one set of proxy materials?

        If you receive more than one set of proxy materials, your shares are registered in more than one name or are registered in different accounts. Please complete, sign and returneach proxy card to ensure that 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 meeting. If you are the record holder of your shares, you may revoke your proxy in any one of three ways:

•

You may submit another properly completed proxy card with a later date.



•

You may send a timely written notice that you are revoking your proxy to Omnicell's Corporate Secretary at 590 E. Middlefield Road, Mountain View, California 94043.



•

You may attend the Annual Meeting and vote in person. Simply attending the 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 due for next year's Annual Meeting?

        Our annual meeting of stockholders generally is held in May of each year. We will consider for inclusion in our proxy materials for the 2021 Annual Meeting of Stockholders, stockholder proposals that are received at our executive offices no later than December 10, 2020 and that comply with all applicable requirements of Rule 14a-8 promulgated under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). However, if our 2021 Annual Meeting of Stockholders is not held between April 26, 2021 and June 25, 2021, then the deadline will be a reasonable time prior to the time we begin to print and send our proxy materials. Proposals must be sent to our Corporate Secretary at Omnicell, Inc., 590 E. Middlefield Road, Mountain View, California 94043.

        Pursuant to Omnicell's bylaws, stockholders wishing to submit proposals or director nominations that are not to be included in our proxy materials must have given timely notice thereof in writing to our Corporate Secretary. To be timely for the 2021 Annual Meeting of Stockholders, you must notify our Corporate Secretary, in writing, not later than the close of business on February 25, 2021, nor earlier than the close of business on January 26, 2021. We also advise you to review Omnicell's bylaws, which contain additional requirements about advance notice of stockholder proposals and director nominations, including the different notice submission date requirements in the event that we do not hold our 2021 Annual Meeting of Stockholders between April 26, 2021 and June 25, 2021. A stockholder's notice to our Corporate Secretary must set forth the information required by Omnicell's bylaws with respect to each matter the stockholder proposes to bring before the annual meeting.

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How are votes counted?

        Votes will be counted by the inspector of elections appointed for the Annual Meeting, who will separately count, for the proposal to elect directors, votes "For," "Withheld," and broker non-votes; and, with respect to the other proposals, votes "For" and "Against," abstentions and broker non-votes. Abstentions on Proposal Nos. 2 and 3 will be counted towards the vote and will have the same effect as "Against" votes. Broker non-votes have no effect on the outcome of the vote for any proposal.

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 by the NYSE 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?

•

For the election of directors, the three (3) nominees receiving the most "For" votes (from the holders of votes of shares present in person or represented by proxy and entitled to vote on the election of directors) will be elected. Only votes "For" will affect the outcome. Broker non-votes and "Withheld" votes will have no effect.



•

For the approval of the advisory vote to approve named executive officer compensation, Proposal No. 2 must receive a "For" vote from the majority of the outstanding shares of common stock present in person or represented by proxy and entitled to vote at the Annual Meeting. If you abstain from voting, it will have the same effect as an "Against" vote. Broker non-votes will have no effect.



•

For the ratification of the selection of Deloitte & Touche LLP as the independent registered public accounting firm of the Company for its fiscal year ending December 31, 2020, Proposal No. 3 must receive a "For" vote from the majority of shares present in person or represented by proxy and entitled to vote either in person or by proxy. If you abstain from voting, it will have the same effect as an "Against" vote. Broker non-votes will have no effect.

What is the quorum requirement?

        A quorum of stockholders is necessary to hold a valid meeting. A quorum will be present if at least a majority of the outstanding shares are represented by stockholders present at the meeting or represented by proxy. On the record date, there were 42,601,447 shares outstanding and entitled to vote. Thus, the holders of 21,300,724 shares must be present in person or represented by proxy at the meeting or by proxy to have a quorum.

        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 meeting. Abstentions and broker non-votes will be counted towards the quorum requirement. If there is no quorum, the holders of a majority of shares present at the meeting in person or represented by proxy may adjourn the meeting to another date.

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

        Preliminary voting results will be announced at the Annual Meeting. Final voting results will be published in a current report on Form 8-K that we expect to file within four business days of the Annual Meeting. If final voting results are not available to us in time to file a current report on Form 8-K within four business days after the Annual Meeting, we intend to file a current report on

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Form 8-K to publish preliminary results and, within four business days after the final results are known to us, file an additional current report on Form 8-K to publish the final results.

What proxy materials are available on the Internet?

        This proxy statement and our Annual Report on Form 10-K are available athttp://ir.omnicell.com/financials-filings/annual-reports-and-proxies.

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BOARD AND CORPORATE GOVERNANCE MATTERS

PROPOSAL NO. 1: ELECTION OF DIRECTORS

        Omnicell's Board presently has nine members and is divided into three classes, each with a three-year term, currently Class I, with a term expiring in 2020, Class II, with a term expiring in 2021 and Class III, with a term expiring in 2022.

        The three directors currently serving in Class I, the class whose term of office expires in 2020, have each been nominated for re-election at the Annual Meeting: Joanne B. Bauer, Robin G. Seim and Sara J. White. Ms. Bauer and Ms. White were previously elected by our stockholders. Mr. Seim was appointed to the Board effective March 18, 2019. If elected at the Annual Meeting, each of these three nominees would serve until the 2023 Annual Meeting of Stockholders and until his or her successor is elected and has qualified, or, if sooner, until the director's death, resignation or removal.

        Although directors are elected by a plurality of votes, it is our policy that any nominee for director in an uncontested election who receives a greater number of votes "withheld" from his or her election than votes "for" such election shall submit his or her offer of resignation for consideration by our Corporate Governance Committee, which will then consider all of the relevant facts and circumstances and recommend to our Board the action to be taken with respect to such offer of resignation. Our Board will then act on our Corporate Governance Committee's recommendation within ninety (90) days following certification of the stockholder vote. Promptly following our Board's decision, we will disclose that decision and an explanation of such decision in a filing with the Securities and Exchange Commission or a press release.

        Vacancies on the Board may be filled only by persons elected by a majority of the remaining directors. A director elected by the Board to fill a vacancy in a class, including a vacancy created by an increase in the number of directors, shall serve for the remainder of the full term of that class and until the director's successor is elected and qualified. It is the Company's policy to encourage directors and nominees for director to attend the Company's Annual Meeting of Stockholders. Five of the nine then-current directors attended our 2019 Annual Meeting of Stockholders.

        Our Corporate Governance Committee seeks to assemble a board of directors that, as a whole, possesses the appropriate balance of professional and industry knowledge, financial expertise and management experience necessary to oversee and direct the Company's business. To that end, the Corporate Governance Committee has evaluated the Board's current members in the broader context of the Board's overall composition. The Corporate Governance Committee maintains a goal of recruiting members who complement and strengthen the skills of other members and who also exhibit integrity, collegiality, sound business judgment and other qualities that the Corporate Governance Committee views as critical to effective functioning of the Board.

        For information about the nominees and each director whose term is continuing after the Annual Meeting, including information regarding the specific and particular experience, qualifications, attributes or skills of each director nominee and continuing director that led the Corporate Governance Committee to believe that such individuals should serve on the Board, please refer to the section below entitled "Information about our Directors and Nominees."

THE BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS
A VOTE "FOR" EACH NAMED NOMINEE.

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INFORMATION ABOUT OUR DIRECTORS AND NOMINEES

        The following table and the brief biographies that follow provide information, as of the date of this proxy statement, about each director nominee and each continuing director.

Director Nominees

Class I Nominees for Election for a Three-Year Term Expiring at the 2023 Annual Meeting

Joanne B. Bauer

        Joanne B. Bauer, age 64, has served as a director of Omnicell since January 2014. Since October 2013, Ms. Bauer has served as a Director of Advocate Aurora Health, an integrated, not-for-profit, health care provider serving communities throughout eastern Wisconsin and northern Illinois. From October 2001 until June 2014, Ms. Bauer served as President of Global Health Care at Kimberly-Clark Corporation, a global consumer packaged goods company. Ms. Bauer joined Kimberly-Clark in 1981 and held various marketing and management positions within its adult care and health care businesses. Ms. Bauer received a B.A. degree from Lawrence University and an M.B.A. from the University of Wisconsin, Oshkosh.

        The Corporate Governance Committee believes Ms. Bauer's leadership and management in the healthcare industry, including serving as the president of the healthcare segment of a large multinational corporation and various management and marketing roles provide the Board with valuable insight regarding the healthcare industry.

Robin G. Seim

        Robin G. Seim, age 60, has served as a director of Omnicell since March 2019. Mr. Seim initially joined Omnicell in January 2006 and served in various financial and operational leadership roles, including Chief Financial Officer from January 2006 to August 2015 and President, Global Automation and Medication Adherence from March 2016 until his retirement in March 2019. Prior to joining Omnicell, Mr. Seim served as Chief Financial Officer of several technology companies, including Villa Montage Systems, Inc. from 1999 to 2001, Candera, Inc. from 2001 to 2004 and Mirra, Inc., in 2005. Prior to 1999, Mr. Seim held a number of management positions with Nortel Networks, Bay Networks, and IBM. Mr. Seim received a B.S. in accounting from California State University, Sacramento.

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        The Corporate Governance Committee believes Mr. Seim brings to the Board a deep understanding of the Company's financial and business operations and the healthcare industry, gained through his 13 years of experience as an executive officer of Omnicell in various financial and operational leadership roles. The Corporate Governance Committee believes that Mr. Seim's extensive knowledge of the Company and its industry, combined with his prior financial expertise and leadership experience, provide the Board with invaluable insights into the Company's financial and business operations, the healthcare industry, as well as financial and operational matters generally.

Sara J. White

        Sara J. White, age 74, has served as a director of Omnicell since April 2003. Since April 2004, Ms. White has served as a pharmacy leadership coach. From 1992 to March 2004, Ms. White was a clinical professor at the School of Pharmacy at the University of California, San Francisco. From 1995 to March 2004, Ms. White was an adjunct professor at the University of the Pacific, School of Pharmacy. From 1992 to 2003, Ms. White was the Director of Pharmacy at Stanford Hospital and Clinics. Ms. White received a B.S. in pharmacy from Oregon State University and an M.S. and Residency in hospital pharmacy management from Ohio State University.

        The Corporate Governance Committee believes Ms. White's leadership and clinical pharmacy expertise proven as the director of pharmacy for more than a decade at one of the top acute-care hospitals in the United States provides valuable scientific and medical knowledge regarding the internal operations and clinical needs of our customers. Further, Ms. White's experience as a clinical professor for two nationally-respected university pharmacy programs offers an important understanding of the future direction of the industry that will help us anticipate the needs and demands of our customers' clinical pharmacy decision-makers.

Continuing Directors

Class II Directors Continuing in Office Until the 2021 Annual Meeting

Randall A. Lipps

        Randall A. Lipps, age 62, has served as Chairman of the Board and a director of Omnicell since founding Omnicell in September 1992 and as its President and Chief Executive Officer since October 2002. From June 2013 to October 2018, Mr. Lipps was a director of Invuity, Inc., a medical device company. Mr. Lipps serves as a member of the Board of Trustees of the American Nurses Foundation. Mr. Lipps received both a B.S. in economics and a B.B.A. from Southern Methodist University.

        The Corporate Governance Committee believes Mr. Lipps' extensive knowledge of the Company, including his founding of the Company and his nearly three decades of leading the Company as the President and CEO, provide the Board with invaluable current knowledge of the Company and extensive knowledge of the industry's needs for improvements in healthcare economics and patient safety. In addition, his role in the operations of the Company provides the Board with the practical understanding of the issues and opportunities that face the Company.

Vance B. Moore

        Vance B. Moore, age 59, has served as a director of Omnicell since May 2012. Since February 2016, Mr. Moore has served as President, Business Integration of Mercy Health, a national healthcare system. From April 2011 to February 2016, Mr. Moore served as Senior Vice President, Operations of Mercy Health. From July 2006 to April 2011, Mr. Moore served as the President and Chief Executive Officer of Resource Optimization & Innovation (ROi), the supply chain operating division of Mercy Health. From August 1998 to March 2007, Mr. Moore served in various capacities at ROi, including Chief Operating Officer. From March 1999 to March 2002, Mr. Moore served as the Vice President,

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Sales and Marketing of the Healthcare Services Division of UPS Logistics Group, a global supply chain management services company. Mr. Moore also served as chairman of the board of ROi until its sale in October 2019 and a director of Ascension Ventures, a strategic healthcare venture fund, until his resignation in February 2020, and serves as a governing committee member of the Coordinating Center for the National Evaluation System for health Technology, a voluntary network of data partners focused on medical device performance. Mr. Moore received a B.S. in industrial management from the University of Arkansas.

        The Corporate Governance Committee believes Mr. Moore's extensive supply chain management expertise and his leadership abilities developed during his service in the chief executive role at a large, national healthcare system's supply chain organization allow him to bring important operations and management skills to the Board.

Mark W. Parrish

        Mark W. Parrish, age 64, has served as a director of Omnicell since January 2013. Mr. Parrish served as Chief Executive Officer of TridentUSA Health Services, a provider of mobile X-ray and laboratory services to the long-term care industry, from 2008 to August 2018, and as Executive Chairman of TridentUSA Health Service from August 2018 to September 2019. In February 2019, TridentUSA Health Services filed for protection under Chapter 11 of the U.S. Bankruptcy Code. Commencing in 1993, Mr. Parrish held management roles of increasing significance with Cardinal Health Inc. and its affiliates, including Chief Executive Officer of Healthcare Supply Chain Services for Cardinal Health from 2006 to 2007. Mr. Parrish also serves as a director of Mylan N.V., a global pharmaceutical company; President of the International Federation of Pharmaceutical Wholesalers, an association of pharmaceutical wholesalers and pharmaceutical supply chain service companies; and senior adviser to Frazier Healthcare Ventures, a health-care oriented growth equity firm. Mr. Parrish received a B.A. from the University of California, Berkeley.

        The Corporate Governance Committee believes Mr. Parrish's extensive leadership experience in the healthcare industry, including serving as the chairman and chief executive officer of a multi-service provider in the long-term care market and various other management roles, provide the Board with valuable insight regarding the healthcare industry and, specifically, the long-term care market.

Class III Directors Continuing in Office Until the 2022 Annual Meeting

James T. Judson

        James T. Judson, age 65 has served as a director of Omnicell since April 2006. From March 2006 to December 2016, Mr. Judson served as a financial executive advisor to small and mid-sized companies. Mr. Judson served as interim Chief Financial Officer of Extreme Networks, Inc., a technology company, from March 2011 to July 2012. From April 2005 to March 2006, Mr. Judson was Omnicell's Interim Chief Financial Officer. From February 2005 to April 2005, Mr. Judson was Omnicell's Vice President of Finance. From 1998 until his retirement in January 2002, Mr. Judson served as Vice President of Finance and Planning for the Worldwide Operations group of Sun Microsystems, Inc., a computer systems company. Mr. Judson received a B.S. in industrial management from Purdue University and an M.B.A. from Indiana University.

        The Corporate Governance Committee believes that Mr. Judson's financial and operational expertise in executive level financial positions at a rapidly growing, global, publicly-traded company provides the Board with valuable insights into the financial operations of the Company and financial matters generally. The Corporate Governance Committee believes that Mr. Judson's knowledge of the Company and its accounting practices as Omnicell's former Interim Chief Financial Officer is especially valuable as Chairman of the Audit Committee.

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Bruce E. Scott

        Bruce E. Scott, age 64, has served as a director of Omnicell since May 2019. From April 2014 to November 2018, Mr. Scott served as President of the EnvisionPharmacies division of EnvisonRxOptions, a health care and pharmacy benefit management company and a subsidiary of the Rite Aid Corporation. From September 2008 to April 2012, Mr. Scott held various executive roles at Medco Health Solutions, Inc., a pharmacy benefit management company, including President of Accredo Infusion Services, President of Critical Care Systems and Senior Vice President and Chief Pharmacist. From 2004 to July 2008, Mr. Scott was Chief Operating Officer of McKesson Medication Management LLC, a provider of pharmacy management services. Previously, he held several senior leadership roles at Allina Hospitals and Clinics, including as the Director of Pharmacy of United Hospital from 1987 to 1998. Mr. Scott serves as Chair of the University of Wisconsin, School of Pharmacy Board of Visitors, an advisory board for the School of Pharmacy. Mr. Scott received a B.S. in pharmacy from the University of Wisconsin and an M.S. in pharmacy administration from the University of Kansas where he also completed a pharmacy residency program.

        The Corporate Governance Committee believes Mr. Scott's leadership and management in the health care industry, and his extensive background and experience with pharmacy benefit management and health care payers in particular, will provide the Board with valuable insight regarding the healthcare industry in general, as well as the internal operations and needs of our pharmacy customers.

Bruce D. Smith

        Bruce D. Smith, age 72, has served as a director of Omnicell since May 2014. From 1995 to July 2017, Mr. Smith served as Senior Vice President and Chief Information Officer of Advocate Health and Hospitals Corporation, an integrated health care system. Mr. Smith received a Bachelor of Business degree from Western Illinois University and an M.B.A. from Loyola University Chicago.

        The Corporate Governance Committee believes Mr. Smith's experience as the chief information officer of a large health care system positions him to contribute effectively to the information technology understanding of the Board.

BOARD LEADERSHIP STRUCTURE

        The Board is currently chaired by the President and Chief Executive Officer ("CEO") of the Company, Mr. Lipps. The Board has also appointed Mr. Judson as lead independent director.

        The Company believes that combining the positions of CEO and Board Chair helps to ensure that the Board and management act with a common purpose. In the Company's view, separating the positions of CEO and Board Chair has the potential to give rise to divided leadership, which could interfere with good decision making or weaken the Company's ability to develop and implement strategy. Instead, the Company believes that combining the positions of CEO and Board Chair provides a single, clear chain of command to execute the Company's strategic initiatives and business plans. In addition, the Company believes that a combined CEO/Board Chair is better positioned to act as a bridge between management and the Board, facilitating the regular flow of information. The Company also believes that it is advantageous to have a Board Chair with an extensive history with, and knowledge of, the Company (as is the case with the Company's CEO) as compared to a relatively less informed independent Board Chair.

        The Board appointed Mr. Judson as the lead independent director to help reinforce the independence of the Board as a whole. The position of lead independent director has been structured to serve as an effective balance to a combined CEO/Board Chair. The lead independent director is empowered to, among other duties and responsibilities, provide general leadership of the affairs of the independent directors, including leadership in anticipating and responding to crisis, discuss and

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collaborate with the Board Chair to set appropriate meeting agendas and meeting schedules, recommend to the Board Chair the retention of outside advisors and consultants who report directly to the Board, preside over Board meetings in the absence of the Board Chair and during independent director closed session portions of the meetings, preside over and establish the agendas for meetings of the independent directors, consult with and coordinate with the committee chairs regarding meeting agendas and informational requirements, act as liaison between the Board Chair and the independent directors, provide advice and consultation to the Board Chair and other senior executives of the Company, monitor information delivered by the management team to the Board and provide input on such information, and, as appropriate upon request, act as a liaison to stockholders, customers and other key constituents of the Company. In addition, it is the responsibility of the lead independent director to coordinate the Board appointment of an Interim CEO and/or Board Chair during extended periods of the Board Chair's absence. As a result, the Company believes that the lead independent director can help ensure the effective independent functioning of the Board in its oversight responsibilities. In addition, the Company believes that the lead independent director is better positioned to build a consensus among directors and to serve as a conduit between the other independent directors and the Board Chair, for example, by facilitating the inclusion on meeting agendas of matters of concern to the independent directors.

INDEPENDENCE OF THE BOARD OF DIRECTORS

        As required under The Nasdaq Stock Market, LLC ("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 directors. The Board consults with the Company's counsel to ensure that the Board's determinations are consistent with relevant securities and other laws and regulations regarding the definition of "independent," including those set forth in the applicable listing standards of the Nasdaq, as in effect from time to time.

        Consistent with these considerations, after review of all relevant transactions or relationships between each director, or any of his or her family members, and the Company, its senior management and its independent auditors, the Board has affirmatively determined that all of the Company's directors and director nominees are independent directors within the meaning of the applicable Nasdaq listing standards, except for Mr. Lipps, the President and CEO of the Company, and Mr. Seim, the Company's former President, Global Automation and Medication Adherence. In making this determination, the Board found that none of the seven independent directors, nominees or appointees for director had a material or other disqualifying relationship with the Company. Mr. Lipps, the Company's President and CEO, is not an independent director by virtue of his employment with the Company. Mr. Seim, who retired from his role as the Company's President, Global Automation and Medication Adherence in March 2019, is not an independent director by virtue of his recent former employment with the Company.

        The Board noted that Mr. Moore, a member of the Board, served as the President and Chief Executive Officer of Resource Optimization & Innovation, LLC ("ROi"), the supply chain division of Mercy Health ("Mercy"), from July 2006 until April 2011, Senior Vice President, Operations, of Mercy from April 2011 until February 2016, and has served as President, Business Integration of Mercy since February 2016. Effective December 31, 2009, the Company entered into a group purchasing organization (GPO) agreement with ROi, whereby the Company agreed to provide products and services to ROi's members, including hospitals within Mercy. Effective July 1, 2019, we entered into a separate corporate master agreement with Mercy (which remains a member of the ROi GPO), whereby we agreed to provide products and services to Mercy under separate terms and conditions. The Company recorded revenue from Mercy of approximately $4.3 million, $1.6 million and $1.1 million for the years ended December 31, 2017, 2018 and 2019, respectively. The Board determined that Mr. Moore did not derive any direct or indirect material benefit from the agreements with ROi and

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Mercy and believes that the agreements are in Omnicell's best interest and on terms no less favorable than could be obtained from other third party group purchasing organizations.

ROLE OF THE BOARD IN RISK OVERSIGHT

        One of the Board's key functions is informed oversight of the Company's risk management process. The Board administers this oversight function directly through the Board as a whole, as well as through the Board's 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. The Audit Committee also monitors compliance with legal and regulatory requirements in addition to oversight of the performance of our audit function. Our Corporate Governance Committee monitors the effectiveness of our corporate governance guidelines, including whether they are successful in preventing illegal or improper liability-creating conduct. Our Compensation Committee assesses and monitors whether any of our compensation policies and programs has the potential to encourage excessive risk-taking.

        Typically, the Corporate Governance Committee receives and discusses with management a quarterly report regarding risk management and the areas of risk the Company has addressed in such quarter. The Corporate Governance Committee reports to the entire Board on the risk management activities of the Company at least annually and the applicable Board committees meet at least annually with the employees responsible for risk management in such committees' respective areas of oversight. Both the Board as a whole and the various standing committees receive periodic reports from management, as well as incidental reports as matters may arise. It is the responsibility of the committee chairs to report findings regarding material risk exposures to the Board as quickly as possible.

DIRECTOR AND EXECUTIVE OFFICER STOCK OWNERSHIP GUIDELINES

        Effective August 5, 2015, we adopted Stock Ownership Guidelines for all Board members and executive officers (designated as such for purposes of Section 16 of the Exchange Act). Pursuant to the guidelines, each Board member and executive officer should beneficially own not less than the following amount of our common stock (as a multiple of their respective compensation):

        Individuals who are subject to these guidelines at the time of their adoption have five years from the date of their respective appointments (or from the date of adoption of the guidelines, whichever is later) to attain the required ownership levels. If an individual becomes subject to a greater ownership amount, due to a promotion or an increase in base salary, the individual is expected to meet such greater ownership amount within the later of the original period or three years from the effective date of the promotion or base salary change.

MEETINGS OF THE BOARD OF DIRECTORS

        The Board met four (4) times during 2019. Each Board member attended 75% or more of the aggregate number of the meetings of the Board and of the committees on which he or she served, as held during the period for which he or she was a director or committee member, respectively.

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        Persons interested in communicating with the independent directors with their concerns or issues may address correspondence to a particular director, or to the independent directors generally, in care of Lead Independent Director, Omnicell, Inc. at 590 E. Middlefield Road, Mountain View, California 94043. If no particular director is named, letters will be forwarded, depending on the subject matter, to the Chair of the Audit, Compensation, or Corporate Governance Committee.

INFORMATION REGARDING COMMITTEES OF THE BOARD OF DIRECTORS

        The Board has four committees: an Audit Committee, a Compensation Committee, a Corporate Governance Committee and a Mergers & Acquisitions Committee. The following table provides membership and meeting information for 2019 for each of the Board committees:

        Below is a description of each committee of the Board. The Board has determined that each member of the Audit Committee, Compensation Committee and Corporate Governance Committee meets the applicable Nasdaq rules and regulations regarding "independence" and that each member is free of any relationship that would impair his or her individual exercise of independent judgment with regard to the Company.

Audit Committee

        The Audit Committee of the Board is currently composed of three directors: Mr. Judson (Chair), Ms. Bauer and Mr. Parrish. Following the Annual Meeting, the Audit Committee will continue to be as currently composed. The Audit Committee met seventeen (17) times during fiscal 2019. The Audit Committee was established by the Board in accordance with Section 3(a)(58)(A) of the Exchange Act, to oversee the Company's corporate accounting and financial reporting processes and audits of its financial statements. For this purpose, the Audit Committee performs several functions. The Audit Committee evaluates the performance of and assesses the qualifications of the independent registered public accounting firm; determines and approves the engagement of the independent registered public

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accounting firm; determines whether to retain or terminate the existing independent registered public accounting firm or to appoint and engage a new independent registered public accounting firm; reviews and approves the retention of the independent registered public accounting firm to perform any proposed permissible non-audit services; monitors the rotation of partners of the independent registered public accounting firm on the Company's audit engagement team as required by law; reviews and approves or rejects transactions between the Company and any related persons; confers with management and the independent registered public accounting firm regarding the effectiveness of internal control over financial reporting; establishes procedures, as required under applicable law, for the receipt, retention and treatment of complaints received by the Company regarding accounting, internal accounting control or auditing matters and the confidential and anonymous submission by employees of concerns regarding questionable accounting or auditing matters; and meets to review the Company's annual audited financial statements and quarterly unaudited financial statements with management and the independent registered public accounting firm, including reviewing the Company's disclosures under "Management's Discussion and Analysis of Financial Condition and Results of Operations" in the Company's Annual Report on Form 10-K. The Audit Committee has adopted a written Audit Committee Charter that can be found in the "Corporate Governance" section on Omnicell's corporate website atwww.omnicell.com, under "Investor Relations."

        The Board reviews the Nasdaq listing standards definition of independence for Audit Committee members on an annual basis and has determined that all members of the Company's Audit Committee are independent (as independence is currently defined in Rule 5605(c)(2)(A)(i) of Nasdaq listing standards). The Board has also determined that Mr. Judson, the Audit Committee Chairperson, qualifies as an "audit committee financial expert," as defined in applicable SEC rules. The Board made a qualitative assessment of Mr. Judson's level of knowledge and experience based on a number of factors, including his formal education and professional experience.

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Report of the Audit Committee of the Board of Directors⁽¹⁾

        The Audit Committee has prepared the following report on its activities with respect to our audited financial statements for the year ended December 31, 2019.

        Our management is responsible for the preparation, presentation and integrity of our financial statements and is also responsible for maintaining appropriate accounting and financial reporting practices and policies. Management is also responsible for establishing and maintaining adequate internal controls and procedures designed to provide reasonable assurance that we are in compliance with accounting standards and applicable laws and regulations.

        Deloitte & Touche LLP, our independent registered public accounting firm for 2019, is responsible for expressing opinions on the conformity of our audited financial statements with U.S. generally accepted accounting principles and the effectiveness of our internal control over financial reporting.

        The Audit Committee has reviewed and discussed the audited financial statements for the fiscal year ended December 31, 2019 with management of the Company. The Audit Committee has discussed with the independent registered public accounting firm the matters required to be discussed pursuant to applicable auditing standards, as adopted by the Public Company Accounting Oversight Board ("PCAOB"). The Audit Committee has also received the written disclosures and the letter from the independent registered public accounting firm regarding the independent registered public accounting firm's independence as required by PCAOB Ethics and Independence Rule 3526,Communication with Audit Committees Concerning Independence

and has discussedStockholder Communications with the independent registered public accounting firm its independence.Board of Directors

        Based on the foregoing, the Audit Committee has recommended to the Board that the audited financial statements be included in the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2015.

⁽¹⁾22

The material in this report is not "soliciting material," is not deemed "filed" with the Commission

Corporate Governance Guidelines

22

Policy Against Hedging Transactions

23

Certain Relationships and is not to be incorporated by reference in any filing of the Company under the Securities Act or the Exchange Act, whether made before or after the date hereof and irrespective of any general incorporation language in any such filing.

Director Compensation

EXECUTIVE OFFICERS

Compensation CommitteeEXECUTIVE COMPENSATION

        The Compensation Committee currently is composed of three directors: Mr. Lindholm (Chair) and Messrs. Petersmeyer and Moore. Following our 2016 Annual Meeting, the Compensation Committee will continue to be composed of Mr. Lindholm (Chair) and Messrs. Petersmeyer and Moore. All members of the Company's Compensation Committee are independent (as independence is currently defined in Rule 5605(a)(2) of the NASDAQ listing standards). The Compensation Committee met eleven (11) times during the fiscal year ended December 31, 2015. The Compensation Committee Charter can be found in the "Corporate Governance" section on Omnicell's corporate website atwww.omnicell.com, under "Investor Relations."PROPOSAL NO. 2: ADVISORY VOTE ON EXECUTIVE COMPENSATION

        The Compensation Committee of the Board acts on behalf of the Board to review, adopt and oversee the Company's compensation strategy, policies, plans and programs, including:

•

reviewing and approving the overall compensation philosophy for the Company's executive officers and directors;



•

overseeing the adoption and administration of, and establishing guidelines relating to, the Company's stock option and purchase plans, profit sharing plans, stock bonus plans, deferred compensation plans and other similar programs, including approving and granting options, restricted stock, restricted stock units or other equity awards under such plans to the Company's executive officers, employees and consultants; and



•

preparing the Company's Compensation Discussion and Analysis included in this proxy statement.

Executive Summary

Executive Compensation-Setting Process

Elements of Compensation and 2019 Determinations

Compensation Committee ProcessesReport

Executive Compensation Tables

Summary Compensation Table

Grants of Plan-Based Awards

Narrative Disclosure to Summary Compensation Table and ProceduresGrants of Plan-Based Awards Table

        TheOutstanding Equity Awards at Fiscal Year End

Option Exercises and Stock Vested

Severance and Change of Control Arrangements

Potential Payments Upon Termination or Change of Control

Risk Analysis of Our Compensation Committee generally meetsPlans

CEO Pay Ratio

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QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS AND VOTING

Why am I receiving these materials?

        The Company has sent you this proxy statement and the enclosed proxy card because the Board of Directors (the "Board") of Omnicell, Inc. is soliciting your proxy to vote at the 2020 Annual Meeting of Stockholders (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. Instead, you may simply complete, sign and return the enclosed proxy card, or follow the instructions below to submit your proxy over the telephone or the Internet.

        The Company intends to mail this proxy statement and accompanying proxy card on or about April 9, 2020 to all stockholders of record entitled to vote at the Annual Meeting.

Who can vote at the Annual Meeting?

        Only stockholders of record at the close of business on March 30, 2020 will be entitled to vote at the Annual Meeting. On the record date, there were 42,601,447 shares of common stock outstanding and entitled to vote.

Stockholder of Record: Shares Registered in Your Name

        If on March 30, 2020 your shares were registered directly in your name with Omnicell's transfer agent, Computershare Trust Company, N.A., then you are a stockholder of record. As a stockholder of record, you may vote in person at the meeting or vote by proxy. Whether or not you plan to attend the meeting, we urge you to fill out and return the enclosed proxy card or vote by proxy over the telephone or on the Internet as instructed below to ensure your vote is counted.

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

        If on March 30, 2020 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 these 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 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 in person at the meeting unless you request and obtain a valid proxy from your broker or other agent.

Directions to the Annual Meeting

        The Annual Meeting will be held at least monthly, and with greater frequency if necessary. The agenda for each meeting is usually outlined by the Chair of the Compensation Committee and then more fully developed by the Company's headquarters located at 590 E. Middlefield Road, Mountain View, California 94043.

        If you need directions to the meeting, please visithttps://goo.gl/maps/pbCcc.

While we intend to hold our Annual Meeting in person, as part of our precautions regarding the coronavirus or COVID-19, we are planning for the possibility that the Annual Meeting may be held solely by means of remote communication if we determine it is not possible or advisable to hold an in-person meeting. If we take this step, we will announce the decision to do so in advance of our Annual Meeting, and details on how to participate will be posted on our website and filed with the SEC as additional proxy material.

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What am I voting on?

        There are three (3) matters scheduled for a vote:

•

The election of three (3) Class I directors to hold office until the 2023 Annual Meeting of Stockholders;



•

An advisory vote to approve named executive officer compensation; and



•

The ratification of the selection by the Audit Committee of the Board of Deloitte & Touche LLP as the independent registered public accounting firm of the Company for the year ending December 31, 2020.

What if another matter is properly brought before the meeting?

        The Board 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" all the nominees to the Board or you may "Withhold" your vote for any nominee you specify. For each of the other matters to be voted on, you may vote "For" or "Against" or abstain from voting. 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 Annual Meeting, vote by proxy using the enclosed proxy card, vote by proxy over the telephone, or vote by proxy over the Internet. Whether or not you plan to attend the meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the meeting and vote in person even if you have already voted by proxy.

•

To vote in person, come to the Annual Meeting and we will give you a ballot when you arrive.



•

To vote using the proxy card, simply complete, sign and date the enclosed proxy card 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.



•

To vote over the telephone, dial toll-free 1-800-652-VOTE (1-800-652-8683) using a touch-tone phone and follow the recorded instructions. You will be asked to provide the control number from the enclosed proxy card. Your vote must be received by 11:59 p.m. Pacific Time, on May 25, 2020 to be counted.



•

To vote over the Internet, go tohttp://www.investorvote.com/OMCL and follow the steps outlined to complete an electronic proxy card. You will be asked to provide the company number and control number from the enclosed proxy card. Your vote must be received by 11:59 p.m. Pacific Time, on May 25, 2020 to be counted.

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 proxy card and voting instructions with these proxy materials from that organization rather than from Omnicell. Simply complete and mail the proxy card to ensure that your vote is counted. Alternatively, you may vote by telephone or over the Internet as instructed by your broker or bank. To vote in person at the Annual Meeting, you must obtain a valid proxy from

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your broker, bank, or other agent. Follow the instructions from your broker or bank included with these proxy materials, or contact your broker or bank to request a proxy form.

We provide Internet proxy voting to allow you to vote your shares on-line, 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.

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 30, 2020.

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, through the Internet or in person at the Annual Meeting, your shares will not be voted.

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

        If you are a beneficial owner and do not instruct your broker, bank, or other agent how to vote your shares, the question of whether your broker or nominee will still be able to vote your shares depends on whether the New York Stock Exchange ("NYSE") deems the particular proposal to be a "routine" matter. Brokers and nominees can use their discretion to vote "uninstructed" shares with respect to matters that are considered to be "routine," but not with respect to "non-routine" matters. Under the rules and interpretations of the NYSE, "non-routine" matters are matters that may substantially affect the rights or privileges of stockholders, such as mergers, stockholder proposals, elections of directors (even if not contested), executive compensation (including any advisory stockholder votes on executive compensation and on the frequency of stockholder votes on executive compensation), and certain corporate governance proposals, even if management-supported. Accordingly, your broker or nominee may not vote your shares on Proposals 1 or 2 without your instructions, but may vote your shares on Proposal 3 even in the absence of your instructions.

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 without marking any voting selections, your shares will be voted as follows:

•

"For" the election of all three (3) Class I directors;



•

"For" an advisory resolution approving named executive officer compensation; and



•

"For" the ratification of the selection of Deloitte & Touche LLP as the independent registered public accounting firm of the Company for the year ending December 31, 2020.

        If any other matter is properly presented at the meeting, your proxy holder (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 mailed 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

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

What does it mean if I receive more than one set of proxy materials?

        If you receive more than one set of proxy materials, your shares are registered in more than one name or are registered in different accounts. Please complete, sign and returneach proxy card to ensure that 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 meeting. If you are the record holder of your shares, you may revoke your proxy in any one of three ways:

•

You may submit another properly completed proxy card with a later date.



•

You may send a timely written notice that you are revoking your proxy to Omnicell's Corporate Secretary at 590 E. Middlefield Road, Mountain View, California 94043.



•

You may attend the Annual Meeting and vote in person. Simply attending the 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 due for next year's Annual Meeting?

        Our annual meeting of stockholders generally is held in May of each year. We will consider for inclusion in our proxy materials for the 2021 Annual Meeting of Stockholders, stockholder proposals that are received at our executive offices no later than December 10, 2020 and that comply with all applicable requirements of Rule 14a-8 promulgated under the Securities Exchange Act of 1934, as amended (the "Exchange Act"). However, if our 2021 Annual Meeting of Stockholders is not held between April 26, 2021 and June 25, 2021, then the deadline will be a reasonable time prior to the time we begin to print and send our proxy materials. Proposals must be sent to our Corporate Secretary at Omnicell, Inc., 590 E. Middlefield Road, Mountain View, California 94043.

        Pursuant to Omnicell's bylaws, stockholders wishing to submit proposals or director nominations that are not to be included in our proxy materials must have given timely notice thereof in writing to our Corporate Secretary. To be timely for the 2021 Annual Meeting of Stockholders, you must notify our Corporate Secretary, in writing, not later than the close of business on February 25, 2021, nor earlier than the close of business on January 26, 2021. We also advise you to review Omnicell's bylaws, which contain additional requirements about advance notice of stockholder proposals and director nominations, including the different notice submission date requirements in the event that we do not hold our 2021 Annual Meeting of Stockholders between April 26, 2021 and June 25, 2021. A stockholder's notice to our Corporate Secretary must set forth the information required by Omnicell's bylaws with respect to each matter the stockholder proposes to bring before the annual meeting.

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How are votes counted?

        Votes will be counted by the inspector of elections appointed for the Annual Meeting, who will separately count, for the proposal to elect directors, votes "For," "Withheld," and broker non-votes; and, with respect to the other proposals, votes "For" and "Against," abstentions and broker non-votes. Abstentions on Proposal Nos. 2 and 3 will be counted towards the vote and will have the same effect as "Against" votes. Broker non-votes have no effect on the outcome of the vote for any proposal.

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 by the NYSE 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?

•

For the election of directors, the three (3) nominees receiving the most "For" votes (from the holders of votes of shares present in person or represented by proxy and entitled to vote on the election of directors) will be elected. Only votes "For" will affect the outcome. Broker non-votes and "Withheld" votes will have no effect.



•

For the approval of the advisory vote to approve named executive officer compensation, Proposal No. 2 must receive a "For" vote from the majority of the outstanding shares of common stock present in person or represented by proxy and entitled to vote at the Annual Meeting. If you abstain from voting, it will have the same effect as an "Against" vote. Broker non-votes will have no effect.



•

For the ratification of the selection of Deloitte & Touche LLP as the independent registered public accounting firm of the Company for its fiscal year ending December 31, 2020, Proposal No. 3 must receive a "For" vote from the majority of shares present in person or represented by proxy and entitled to vote either in person or by proxy. If you abstain from voting, it will have the same effect as an "Against" vote. Broker non-votes will have no effect.

What is the quorum requirement?

        A quorum of stockholders is necessary to hold a valid meeting. A quorum will be present if at least a majority of the outstanding shares are represented by stockholders present at the meeting or represented by proxy. On the record date, there were 42,601,447 shares outstanding and entitled to vote. Thus, the holders of 21,300,724 shares must be present in person or represented by proxy at the meeting or by proxy to have a quorum.

        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 meeting. Abstentions and broker non-votes will be counted towards the quorum requirement. If there is no quorum, the holders of a majority of shares present at the meeting in person or represented by proxy may adjourn the meeting to another date.

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

        Preliminary voting results will be announced at the Annual Meeting. Final voting results will be published in a current report on Form 8-K that we expect to file within four business days of the Annual Meeting. If final voting results are not available to us in time to file a current report on Form 8-K within four business days after the Annual Meeting, we intend to file a current report on

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Form 8-K to publish preliminary results and, within four business days after the final results are known to us, file an additional current report on Form 8-K to publish the final results.

What proxy materials are available on the Internet?

        This proxy statement and our Annual Report on Form 10-K are available athttp://ir.omnicell.com/financials-filings/annual-reports-and-proxies.

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BOARD AND CORPORATE GOVERNANCE MATTERS

PROPOSAL NO. 1: ELECTION OF DIRECTORS

        Omnicell's Board presently has nine members and is divided into three classes, each with a three-year term, currently Class I, with a term expiring in 2020, Class II, with a term expiring in 2021 and Class III, with a term expiring in 2022.

        The three directors currently serving in Class I, the class whose term of office expires in 2020, have each been nominated for re-election at the Annual Meeting: Joanne B. Bauer, Robin G. Seim and Sara J. White. Ms. Bauer and Ms. White were previously elected by our stockholders. Mr. Seim was appointed to the Board effective March 18, 2019. If elected at the Annual Meeting, each of these three nominees would serve until the 2023 Annual Meeting of Stockholders and until his or her successor is elected and has qualified, or, if sooner, until the director's death, resignation or removal.

        Although directors are elected by a plurality of votes, it is our policy that any nominee for director in an uncontested election who receives a greater number of votes "withheld" from his or her election than votes "for" such election shall submit his or her offer of resignation for consideration by our Corporate Governance Committee, which will then consider all of the relevant facts and circumstances and recommend to our Board the action to be taken with respect to such offer of resignation. Our Board will then act on our Corporate Governance Committee's recommendation within ninety (90) days following certification of the stockholder vote. Promptly following our Board's decision, we will disclose that decision and an explanation of such decision in a filing with the Securities and Exchange Commission or a press release.

        Vacancies on the Board may be filled only by persons elected by a majority of the remaining directors. A director elected by the Board to fill a vacancy in a class, including a vacancy created by an increase in the number of directors, shall serve for the remainder of the full term of that class and until the director's successor is elected and qualified. It is the Company's policy to encourage directors and nominees for director to attend the Company's Annual Meeting of Stockholders. Five of the nine then-current directors attended our 2019 Annual Meeting of Stockholders.

        Our Corporate Governance Committee seeks to assemble a board of directors that, as a whole, possesses the appropriate balance of professional and industry knowledge, financial expertise and management experience necessary to oversee and direct the Company's business. To that end, the Corporate Governance Committee has evaluated the Board's current members in the broader context of the Board's overall composition. The Corporate Governance Committee maintains a goal of recruiting members who complement and strengthen the skills of other members and who also exhibit integrity, collegiality, sound business judgment and other qualities that the Corporate Governance Committee views as critical to effective functioning of the Board.

        For information about the nominees and each director whose term is continuing after the Annual Meeting, including information regarding the specific and particular experience, qualifications, attributes or skills of each director nominee and continuing director that led the Corporate Governance Committee to believe that such individuals should serve on the Board, please refer to the section below entitled "Information about our Directors and Nominees."

THE BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS
A VOTE "FOR" EACH NAMED NOMINEE.

Table of Contents

INFORMATION ABOUT OUR DIRECTORS AND NOMINEES

        The following table and the brief biographies that follow provide information, as of the date of this proxy statement, about each director nominee and each continuing director.

Director Nominees