June 3, 2026
Liftoff Mobile, Inc.
900 Middlefield Road
Redwood City, California 94063
To the Addressee Stated Above:
We have acted as counsel to Liftoff Mobile, Inc., a Delaware corporation (the “Company”), in connection with the Registration Statement on Form S-8 (the “Registration Statement”) filed by the Company with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended, relating to the issuance by the Company of an aggregate of up to 74,951,698 shares (the “Shares”) of common stock, par value $0.0001 per share, of the Company (the “Common Stock”), consisting of: (i) up to 24,200,000 shares of Common Stock that may be issued by the Company pursuant to the Liftoff Mobile, Inc. 2026 Omnibus Incentive Plan (the “2026 Omnibus Plan”), (ii) up to 4,900,000 shares of Common Stock that may be issued by the Company pursuant to the Liftoff Mobile, Inc. 2026 Employee Stock Purchase Plan (the “ESPP”) and (iii) up to 45,851,698 shares of Common Stock that may be issued by the Company pursuant to the Booster Parent Holdings, Inc. 2021 Stock Incentive Plan (the “Legacy Equity Plan” and, together with the 2026 Omnibus Plan and the ESPP, the “Plans”).
We have examined the Registration Statement, a form of the Amended and Restated Certificate of Incorporation of the Company (the “Amended Certificate”) and the Plans, each of which has been filed with the Commission as an exhibit to the Registration Statement. In addition, we have examined, and have relied as to matters of fact upon, originals, or duplicates or certified or conformed copies, of such records, agreements, documents and other instruments and such certificates or comparable documents of public officials and of officers and representatives of the Company and have made such other investigations as we have deemed relevant and necessary in connection with the opinions hereinafter set forth.
In rendering the opinion set forth below, we have assumed the genuineness of all signatures, the legal capacity of natural persons, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as duplicates or certified or conformed copies and the authenticity of the originals of such latter documents. We have also assumed that the Amended Certificate is filed with the Secretary of State for the State of Delaware in the form filed with the Commission as an exhibit to the Registration Statement prior to the issuance of any of the Shares.