X0306 4 2021-07-07 0 0001561550 Datadog, Inc. DDOG 0001120741 OBSTLER DAVID M C/O DATADOG, INC. 620 8TH AVENUE, 45TH FLOOR NEW YORK NY 10018 0 1 0 0 Chief Financial Officer Class A Common Stock 2021-07-07 4 S 0 4888 107.1971 D 10112 I By GRAT Class A Common Stock 2021-07-07 4 S 0 8354 107.656 D 1758 I By GRAT Class A Common Stock 2021-07-07 4 S 0 1358 108.7274 D 400 I By GRAT Class A Common Stock 2021-07-07 4 S 0 400 109.7975 D 0 I By GRAT Class A Common Stock 177095 D Shares sold pursuant to a 10b5-1 plan entered into on December 10, 2020. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $106.37 to $107.36. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Shares are held directly by the David Obstler 2019 GRAT, of which Reporting Person is Trustee. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $107.37 to $108.34. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $108.47 to $109.10. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $109.66 to $110.00. The Reporting Person will provide upon request to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price. David Obstler, by /s/ Ron A. Metgzer, Attorney-in-Fact 2021-07-09