X0306 5 2020-12-31 0 0 0 0001561550 Datadog, Inc. DDOG 0001688124 Griffith William J.G. C/O ICONIQ CAPITAL 394 PACIFIC AVENUE, 2ND FLOOR SAN FRANCISCO CA 94111 0 0 1 0 Class A Common Stock 2020-11-24 5 G 0 22230 0.00 D 367072 D Class A Common Stock 1397725 I See footnotes Class A Common Stock 1094133 I See footnotes Class A Common Stock 508142 I See footnotes Class A Common Stock 408849 I See footnotes Class A Common Stock 436857 I See footnotes Class A Common Stock 199500 I See footnotes Class A Common Stock 325500 I See footnotes On November 24, 2020, the Reporting Person made a bona fide gift of 22,230 shares of the Issuer's Class A Common Stock to a donor-advised fund. These shares are held by the Reporting Person through his family trust of which he is a trustee and another estate planning trust having an independent trustee. These shares are held by ICONIQ Strategic Partners II, L.P. ("ICONIQ II"). These shares are held by ICONIQ Strategic Partners II-B, L.P. ("ICONIQ II"). These shares are held by ICONIQ Strategic Partners II Co-Invest, L.P. ("ICONIQ II Co-Invest"). These shares are held by ICONIQ Strategic Partners III, L.P. ("ICONIQ III"). These shares are held by ICONIQ Strategic Partners III-B, L.P. ("ICONIQ III-B"). These shares are held by ICONIQ Strategic Partners IV, L.P. ("ICONIQ IV"). These shares are held by ICONIQ Strategic Partners IV-B, L.P. ("ICONIQ IV-B"). ICONIQ Strategic Partners II GP, L.P. ("ICONIQ II GP") is the sole general partner of each of ICONIQ II, ICONIQ II-B and ICONIQ II Co-Invest. ICONIQ Strategic Partners II TT GP, Ltd. ("ICONIQ II Parent GP") is the sole general partner of ICONIQ II GP. ICONIQ Strategic Partners III GP, L.P. ("ICONIQ III GP") is the sole general partner of each of ICONIQ III and ICONIQ III-B. ICONIQ Strategic Partners III TT GP, Ltd. ("ICONIQ III Parent GP") is the sole general partner of ICONIQ III GP. ICONIQ Strategic Partners IV GP, L.P. ("ICONIQ IV GP") is the sole general partner of ICONIQ IV and ICONIQ IV-B. ICONIQ Strategic Partners IV TT GP, Ltd. ("ICONIQ IV Parent GP") is the general partner of ICONIQ IV GP. Divesh Makan ("Makan") and William J.G. Griffith ("Griffith") are the sole equity holders and directors of ICONIQ II Parent GP and ICONIQ III Parent GP and Makan, Griffith and Matthew Jacobson are the sole equity holders and directors of ICONIQ IV Parent GP. The Reporting Person is a General Partner and a Managing Director at ICONIQ Capital. The Reporting Person disclaims beneficial ownership of the securities reported herein for purposes of Section 16 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of his pecuniary interest therein, if any. This report shall not be deemed an admission that the Reporting Person is a beneficial owner of such securities for the purpose of Section 16 of the Exchange Act, or for any other purpose. /s/ William J.G. Griffith 2021-02-16