EX-5.1

EXHIBIT 5.1

LOGO

Nicole C. Brookshire

+1 617 937 2357

nbrookshire@cooley.com

September 12, 2019

Cardlytics, Inc.

675 Ponce de Leon Avenue,

NE, Suite 6000

Atlanta, Georgia 30308

Ladies and Gentlemen:

You have requested our opinion, as counsel to Cardlytics, Inc., a Delaware corporation (the “Company”), with respect to certain matters in connection with the offering of up to 3,098,519 shares (the “Shares”) of the Company’s common stock, par value $0.0001, including up to 404,154 Shares that may be sold pursuant to the exercise of an option to purchase additional shares, pursuant to a Registration Statement on Form S-3 (Registration Statement No. 333-232861) (the “Registration Statement”), filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Act”), the prospectus included within the Registration Statement (the “Base Prospectus”), and the prospectus supplement, dated September 10, 2019, and filed with the Commission pursuant to Rule 424(b) of the Rules and Regulations of the Act (together with the Base Prospectus, the “Prospectus”). Of the Shares, up to 1,904,154 of the Shares are to be sold by the Company (the “Company Shares”) and up to 1,194,365 of the Shares are to be sold by certain selling stockholders (the “Selling Stockholder Shares”) as described in the Registration Statement and the Prospectus.

In connection with this opinion, we have examined and relied upon (a) the Registration Statement and the Prospectus, (b) the Company’s Amended and Restated Certificate of Incorporation and the Company’s Amended and Restated Bylaws, each as currently in effect, and (c) originals or copies certified to our satisfaction of such 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 and authenticity of all documents submitted to us as originals, and the conformity to originals of all documents submitted to us as copies and the due execution and delivery of all documents where due execution and delivery are a prerequisite to the effectiveness thereof. As to certain factual matters, we have relied upon a certificate of an officer of the Company and have not sought independently to verify such matters.

Our opinion is expressed only with respect to the General Corporation Law of the State of Delaware. Our opinion is based on these laws as in effect on the date hereof. 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:

1. The Company Shares, when sold and issued against payment therefor as described in the Registration Statement and the Prospectus, will be validly issued, fully paid and non-assessable.

2. The Selling Stockholder Shares have been validly issued and are fully paid and non-assessable.

Cooley LLP 500 Boylston Street Boston, MA 02116-3736

t: (617) 937-2300 f: (617) 937-2400 cooley.com


Sincerely,

Cooley LLP

By:		/s/ Nicole C. Brookshire
		Nicole C. Brookshire