X0306 4 2021-05-12 0 0001561627 ExOne Co XONE 0001250606 IRVIN JOHN 127 INDUSTRY BOULEVARD NORTH HUNTINGDON PA 15642 1 0 0 0 Common Stock, par value $0.01 2021-05-12 4 A 0 4958 0.00 A 19958 D Common Stock, par value $0.01 128450 I By 20 20 Holdings, LLC Grant of restricted stock under The ExOne Company 2013 Equity Incentive Plan. 100% of the restricted stock vests on May 11, 2022. 20 20 Holdings, LLC is the owner of the listed shares. 20 20 Holdings is a limited liability company beneficially owned by Mr. Irvin's wife and Mr. Irvin, and of which Mr. Irvin is the sole manager and has sole power to vote and dispose of the shares. /s/ Loretta L. Benec, attorney-in-fact for John Irvin 2021-05-14