X0609 4 2026-09-02 0 0001561550 Datadog, Inc. DDOG 0001783984 Le-Quoc Alexis false C/O DATADOG, INC. 620 8TH AVENUE, 45TH FLOOR NEW YORK NY 10018 1 1 0 0 Chief Technology Officer 0 Class A Common Stock 2026-09-02 4 S 0 21772 212.9043 D 488033 D Class A Common Stock 169 I By Trust The Reporting Person was required by the Issuer to sell only the number of shares of common stock necessary to cover applicable tax withholding obligations realized upon the vesting of restricted stock units and performance-based restricted stock units, as well as any related brokerage commission fees. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $210.12 to $213.01. 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 by the Alexis Le-Quoc Revocable Trust. /s/ Kerry Acocella, Attorney-in-Fact 2026-09-04