X0306 4 2021-11-09 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 2021-11-09 4 C 0 3750 0.00 A 3750 I By GRAT Class A Common Stock 2021-11-09 4 S 0 378 191.5993 D 3372 I By GRAT Class A Common Stock 2021-11-09 4 S 0 600 193.1483 D 2772 I By GRAT Class A Common Stock 2021-11-09 4 S 0 700 194.2486 D 2072 I By GRAT Class A Common Stock 2021-11-09 4 S 0 1058 195.1463 D 1014 I By GRAT Class A Common Stock 2021-11-09 4 S 0 514 196.3355 D 500 I By GRAT Class A Common Stock 2021-11-09 4 S 0 500 197.102 D 0 I By GRAT Class A Common Stock 2021-11-10 4 C 0 15000 0.00 A 190391 D Class A Common Stock 2021-11-10 4 S 0 1000 186.179 D 189391 D Class A Common Stock 2021-11-10 4 S 0 1122 187.3598 D 188269 D Class A Common Stock 2021-11-10 4 S 0 4025 188.4476 D 184244 D Class A Common Stock 2021-11-10 4 S 0 1000 189.327 D 183244 D Class A Common Stock 2021-11-10 4 S 0 900 191.0233 D 182344 D Class A Common Stock 2021-11-10 4 S 0 1703 192.0762 D 180641 D Class A Common Stock 2021-11-10 4 S 0 700 193.26 D 179941 D Class A Common Stock 2021-11-10 4 S 0 2945 194.1273 D 176996 D Class A Common Stock 2021-11-10 4 S 0 1505 194.963 D 175491 D Class A Common Stock 2021-11-10 4 S 0 100 195.69 D 175391 D Class B Common Stock 2021-11-09 4 C 0 3750 0.00 D Class A Common Stock 3750 229897 I By GRAT Stock Option (Right to Buy) 1.55 2021-11-10 4 M 0 15000 0.00 D 2028-09-06 Class B Common Stock 15000 665000 D Class B Common Stock 2021-11-10 4 M 0 15000 0.00 A Class A Common Stock 15000 30603 D Class B Common Stock 2021-11-10 4 C 0 15000 0.00 D Class A Common Stock 15000 15603 D Shares are held directly by the David Obstler 2019 GRAT, of which Reporting Person is Trustee. Shares sold pursuant to a 10b5-1 plan entered into on September 10, 2021. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $191.18 to $192.15. 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 $192.61 to $193.58. 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 $193.65 to $194.63. 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 $194.72 to $195.48. 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 $195.88 to $196.71. 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 $196.90 to $197.55. 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. 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 sold pursuant to a 10b5-1 plan entered into on June 14, 2021. Price reported is a weighted-average sales price. The shares were sold at prices ranging from $185.56 to $186.53. 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 $186.89 to $187.78. 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 $187.92 to $188.89. 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 $188.96 to $189.75. 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 $190.55 to $191.48. 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 $191.55 to $192.47. 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 $192.59 to $193.58. 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 $193.59 to $194.55. 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 $194.59 to $195.58. 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. Represents the number of shares of Class A Common Stock underlying restricted stock units ("RSUs"). Each RSU represents the contingent right to receive one share of the Issuer's Class A Common Stock. The shares underlying the RSUs vest in 12 equal quarterly installments beginning on June 1, 2022 and on each September 1, December 1 and March 1 thereafter, subject to the Reporting Person remaining in Continuous Service (as defined in the Issuer's 2019 Equity Incentive Plan) of the Issuer as of each such date. Option vests as to 25% on September 6, 2019 and in equal monthly installments thereafter over three years. David Obstler, by /s/ Ron A. Metzger, Attorney-in-Fact 2021-11-12