Proto Labs Inc

The Notice contains instructions on how to access our proxy materials on the Internet and vote your shares of stock via the Internet and how to request a paper copy of our proxy materials.

A copy of our Annual Report on Form 10-K for the year ended December 31, 2023, as filed with the SEC, is available on the Investor page of the Company’s Internet site, www.protolabs.com, and will be sent to any shareholder without charge upon written request addressed to:

Chief Financial Officer

5540 Pioneer Creek Drive

Maple Plain, Minnesota 55359

(763) 479-3680

You may also obtain our Annual Report on Form 10-K via the Internet at the SEC’s Internet site, www.sec.gov.

Additional copies of the Annual Report on Form 10-K, the Notice, this Proxy Statement and the accompanying proxy may be obtained from the Investor page of the Company’s Internet site, www.protolabs.com, and from Daniel Schumacher, our Chief Financial Officer, at the address above. Copies of exhibits to the Annual Report on Form 10-K may be obtained upon payment to us of the reasonable expense incurred in providing such exhibits.

By Order of the Board of Directors

Jason Frankman

Corporate Secretary

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