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Your Vote Counts! *Please check the meeting materials for any special requirements for meeting attendance. Smartphone users Point your camera here and vote without entering a control number For complete information and to vote, visit www.ProxyVote.com Control # V40838-P04604 MARKFORGED HOLDING CORPORATION 60 TOWER ROAD WALTHAM, MA 02451 MARKFORGED HOLDING CORPORATION 2024 Annual Meeting Vote by June 17, 2024 11:59 PM ET You invested in MARKFORGED HOLDING CORPORATION and it’s 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 stockholder meeting to be held on June 18, 2024. Vote Virtually at the Meeting* June 18, 2024 9:00 AM Eastern Time Virtually at: www.virtualshareholdermeeting.com/MKFG2024 Get informed before you vote View the Annual Report, Notice & Proxy Statement online OR you can receive a free paper or email copy of the material(s) by requesting prior to June 4, 2024. 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.

Vote at www.ProxyVote.com Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click “Delivery Settings”. Voting Items Board Recommends V40839-P04604 THIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote these important matters. 1. To elect three Class III directors to serve for a three-year term ending at the 2027 Annual Meeting of Stockholders. For All Nominees: 01) Alan Masarek 02) Carol Meyers 03) Aaron VanDevender 2. To ratify the appointment of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2024. For 3. To approve an amendment to the Company’s Certificate of Incorporation to limit the liability of certain officers of the Company as permitted by recent amendments to the Delaware General Corporation Law. For 4. To approve an amendment to the Company’s Certificate of Incorporation to approve a reverse stock split of our common stock and an associated reduction in the number of shares of our authorized common stock. For NOTE: Such other business as may properly come before the meeting or any adjournment th