comScore (SCOR) DEFA14A Additional proxy soliciting materials

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934

(Amendment No.     )

Filed by the Registrant  ☒

Filed by a Party other than the Registrant  ☐

Check the appropriate box:

☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☐ Definitive Proxy Statement

☒ Definitive Additional Materials

☐ Soliciting Material under §240.14a-12

COMSCORE, INC.

(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

☒ No fee required.

☐ Fee paid previously with preliminary materials.

☐ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

Your Vote Counts! COMSCORE, INC. 2022 Annual Meeting Vote by June 14, 2022 11:59 PM ET COMSCORE, INC. 11950 DEMOCRACY DR., SUITE 600 RESTON, VA 20190 D83090-P68975 You invested in COMSCORE, INC. and its time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy material for the Annual Meeting to be held on June 15, 2022. Get informed before you vote View the Notice and Proxy Statement and Form 10-K online OR request a free paper or email copy of the material(s) before June 1, 2022. If you would like to request a copy of the material(s) for this and/or future stockholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to sendmaterial@proxyvote.com. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy. For complete information and to vote, visit www.ProxyVote.com Control # Smartphone users Point your camera here and vote without entering a control number Vote in Person at the Annual Meeting* June 15, 2022 10:00 AM, EDT Carr Workplaces 1818 Library Street, Suite 500 Reston, Virginia 20190 *Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares. V1.1

Vote at www.ProxyVote.com THIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming Annual Meeting. Please follow the instructions on the reverse side to vote these important matters. Voting Items The Board Recommends 1. Election of Directors: Nominees: 01) Itzhak Fisher For 02) Pierre Liduena 03) Marty Patterson 2. The approval, on a non-binding advisory basis, of the compensation paid to the Company's named executive officers For 3. The ratification of the appointment of Deloitte & Touche LLP as the Company's independent registered public accounting firm for the fiscal year ending December 31, 2022 For 4. The approval of an amendment to the Amended and Restated 2018 Equity and Incentive Compensation Plan For Note: In their discretion, the proxies may vote on such other matters as may properly come before the meeting or may otherwise be allowed to be considered at the meeting. Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click "Sign up for E-delivery". D83091-P68975