X0609 4 2026-06-12 0 0001561550 Datadog, Inc. DDOG 0001120741 OBSTLER DAVID M false C/O DATADOG, INC. 620 8TH AVENUE, 45TH FLOOR NEW YORK NY 10018 0 1 0 0 Chief Financial Officer 0 Class A Common Stock 2026-06-12 4 C 0 7500 0 A 442091 D Class A Common Stock 2026-06-12 4 G 0 7500 0 D 434591 D Class B Common Stock 2026-06-12 4 C 0 7500 0 D Class A Common Stock 7500 8103 D Class B Common Stock Class A Common Stock 46199 46199 I By Trust Class B Common Stock Class A Common Stock 46198 46198 I By Trust Each share of Class B Common Stock is convertible at any time at the option of the Reporting Person into one share of Class A Common Stock and has no expiration date. Each share of Class B Common Stock will convert automatically into one share of Class A Common Stock upon the earliest of: (i) any transfer, whether or not for value, except for certain "Permitted Transfers" as defined in the Issuer's amended and restated certificate of incorporation, (ii) the death of the Reporting Person in the case of shares held directly or in a trustee capacity, and (iii) the tenth anniversary of the Issuer's initial public offering of its Class A Common Stock. Shares are held directly by Obstler Children 2019 Trust FBO the Reporting Person's child, of which the Reporting Person's spouse is Trustee. Obstler Children 2019 Trust FBO the Reporting Person's child and Obstler Children 2019 Trust FBO the Reporting Person's other child are separate trusts for the benefit of the Reporting Person's children with substantially identical terms. Shares are held directly by Obstler Children 2019 Trust FBO the Reporting Person's other child, of which the Reporting Person's spouse is Trustee. See Footnote 2. /s/ Kerry Acocella, Attorney-in-Fact 2026-06-16