As filed with the Securities and Exchange Commission on March 12, 2021.

Registration No. 333-            

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Datadog, Inc.

(Exact name of registrant as specified in its charter)

620 8th Avenue, 45th Floor

New York, New York 10018

(866) 329-4466

(Address of Principal Executive Offices) (Zip Code)

Datadog, Inc. 2019 Equity Incentive Plan

Datadog, Inc. 2019 Employee Stock Purchase Plan

(Full titles of the plans)

Laszlo Kopits

General Counsel

Datadog, Inc.

620 8th Avenue, 45th Floor

New York, New York 10018

(866) 329-4466

(Name and address of agent for service)

(Telephone number, including area code, of agent for service)

Copies to:

Jodie Bourdet

Nicole Brookshire

Cooley LLP

55 Hudson Yards

New York, New York 10001

(212) 479-6000

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards pursuant to Section 7(a)(2)(B) of the Securities Act.  ☐

CALCULATION OF REGISTRATION FEE

REGISTRATION OF ADDITIONAL SHARES

PURSUANT TO GENERAL INSTRUCTION E

Pursuant to General Instruction E of Form S-8, Datadog, Inc. (the “Registrant”) is filing this Registration Statement with the Securities and Exchange Commission (the “Commission”) to register (i) 15,294,003 additional shares of its Class A common stock under the 2019 Plan, pursuant to the provisions of the 2019 Plan providing for an automatic increase in the number of shares of Class A common stock reserved and available for issuance under the 2019 Plan on January 1, 2021, and (ii) 3,058,800 additional shares of its Class A common stock under the 2019 ESPP, pursuant to the provisions of the 2019 ESPP providing for an automatic increase in the number of shares of Class A common stock reserved and available for issuance under the 2019 ESPP on January 1, 2021. In accordance with the instructional note to Part I of Form S-8 as promulgated by the Commission, the information specified by Part I of the Form S-8 has been omitted from this Registration Statement.

PART II

The following documents filed by the Registrant with the Commission are incorporated by reference into this Registration Statement:

(a) The contents of the Registrant’s Registration Statement on Form S-8 (File Nos. 333-233903 and 333-237176), filed with the Commission on September 23, 2019 and March 13, 2020, respectively.

(b) The Registrant’s Annual Report on Form 10-K for the fiscal year ended December  31, 2020, filed with the Commission on March 1, 2021.

(c) The description of the Registrant’s Class A Common Stock which is contained in a registration statement on Form 8-A filed on September 16, 2019 (File No. 001-39051) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), including any amendment or report filed for the purpose of updating such description.

(d) All other reports and documents subsequently filed by the Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act (other than Current Reports furnished under Item 2.02 or Item 7.01 of Form 8-K and exhibits furnished on such form that relate to such items) on or after the date of this Registration Statement and prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference herein and to be a part of this Registration Statement from the date of the filing of such reports and documents. Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any subsequently filed document that also is deemed to be incorporated by reference herein modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York, State of New York, on March 12, 2021.

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Olivier Pomel and Alexis Lê-Quôc, and each one of them, as his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in their name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement, and to sign any registration statement for the same offering covered by this registration statement that is to be effective on filing pursuant to Rule 462(b) under the Securities Act of 1933, as amended, and all post-effective amendments thereto, and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them, or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

Exhibit 5.1

Nicole C. Brookshire

+1 617 937 2357

nbrookshire@cooley.com

March 12, 2021

Datadog, Inc.

620 8th Avenue, 45th Floor

New York, NY 10018

Ladies and Gentlemen:

We have acted as counsel to Datadog, Inc., a Delaware corporation (the “Company”), in connection with the filing of a Registration Statement on Form S-8 (the “Registration Statement”) with the U.S. Securities and Exchange Commission, covering the offering of up to 18,352,803 shares (the “Shares”) of the Company’s Class A common stock, par value $0.00001 per share (“Common Stock”) consisting of (a) 15,294,003 shares of Common Stock issuable pursuant to the Company’s 2019 Equity Incentive Plan (the “2019 EIP”) and (b) 3,058,800 shares of Common Stock issuable pursuant to the Company’s 2019 Employee Stock Purchase Plan (together with the 2019 EIP, the “Plans”).

In connection with this opinion, we have examined and relied upon (a) the Registration Statement and the related prospectuses, (b) the Company’s Amended and Restated Certificate of Incorporation and Amended and Restated Bylaws, each as currently in effect, (c) the Plans and (d) originals or copies certified to our satisfaction of such other records, documents, certificates, memoranda and other instruments as in our judgment are necessary or appropriate to enable us to render the opinion expressed below. We have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to originals of all documents submitted to us as copies thereof, the accuracy, completeness and authenticity of certificates of public officials and the due authorization, execution and delivery of all documents by all persons other than the Company where due execution and delivery are prerequisites to the effectiveness thereof. As to certain factual matters, we have relied upon a certificate of an officer of the Company and have not independently verified such matters.

Our opinion is expressed only with respect to the General Corporation Law of the State of Delaware. We express no opinion to the extent that any other laws are applicable to the subject matter hereof and express no opinion and provide no assurance as to compliance with any federal or state securities law, rule or regulation.

On the basis of the foregoing, and in reliance thereon, we are of the opinion that the Shares, when sold and issued in accordance with the Plans, the Registration Statement and the related prospectuses, will be validly issued, fully paid, and nonassessable (except as to Shares issued pursuant to certain deferred payment arrangements, which will be fully paid and nonassessable when such deferred payments are made in full).

COOLEY LLP 55 HUDSON YARDS NEW YORK, NY 10001

T: (212) 479-6000 F: (212) 479-6275 COOLEY.COM

Datadog, Inc.

March 12, 2021

Page Two

We consent to the filing of this opinion as an exhibit to the Registration Statement.

Sincerely,

COOLEY LLP

COOLEY LLP 55 HUDSON YARDS NEW YORK, NY 10001

T: (212) 479-6000 F: (212) 479-6275 COOLEY.COM

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement on Form S-8 of our reports dated March 1, 2021 relating to the financial statements of Datadog, Inc. (the “Company”) and the effectiveness of the Company’s internal control over financial reporting, appearing in the Annual Report on Form 10-K of the Company for the year ended December 31, 2020.