EX-5.1

Exhibit 5.1

LOGO

February 29, 2024

APi Group Corporation

1100 Old Highway 8 NW

New Brighton, MN 55112

Re:	APi Group Corporation Prospectus Supplement to Registration Statement on Form S-3

Ladies and Gentlemen:

We have served as counsel to APi Group Corporation, a Delaware corporation (the “Company”), in connection with the filing on January 3, 2022, with the Securities and Exchange Commission (the “Commission”) of a registration statement on Form S-3 (File No. 333-261985) (as amended and/or supplemented, the “Registration Statement”) under the Securities Act of 1933, as amended (the “Securities Act”), relating to the offering from time to time by the selling stockholders named therein (“Selling Stockholders”) of up to an aggregate of 45,000,000 shares of common stock, par value $0.0001 per share (“Common Stock”), of the Company. The Registration Statement was declared effective by the Commission on January 7, 2022. Reference is made to our opinion letter dated January 3, 2022, and included as Exhibit 5.1 to the Registration Statement. We are delivering this supplemental opinion letter in connection with the final prospectus supplement (the “Prospectus Supplement”) dated February 29, 2024, to be filed by the Company with the Commission pursuant to Rule 424 under the Securities Act. The Prospectus Supplement relates to the offering by the Selling Stockholders of 10,569,106 shares of Common Stock (and up to an additional 1,585,365 shares of Common Stock subject to an over-allotment option granted by the Selling Stockholders to the Underwriters (as defined below)) (the “Shares”) covered by the Registration Statement.

The Shares are being sold by the Selling Stockholders to the several underwriters named in, and pursuant to, the Underwriting Agreement, dated as of February 29, 2024 (the “Underwriting Agreement”), by and among the Company and UBS Securities LLC and Citigroup Global Markets Inc., on their own behalf and as representatives of the several underwriters named in Schedule III thereto (the “Underwriters”).

This opinion letter is being furnished in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act.

We have reviewed such documents and made such examination of law as we have deemed appropriate to give the opinions set forth below. We have relied, without independent verification, on certificates of public officials and, as to matters of fact material to the opinion set forth below, on certificates of officers of the Company.

Based upon the foregoing, and subject to the additional qualifications set forth below, we are of the opinion that the Shares have been validly issued, fully paid, and nonassessable.

The opinion expressed above is limited to the Delaware General Corporation Law (which includes reported judicial decisions interpreting the Delaware General Corporation Law) and we have not considered and express no opinion on the effect of any laws or the laws of any other state or jurisdiction, including state and federal laws relating to securities or other federal laws, or the rules and regulations of stock exchanges or any other regulatory body.

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