; . (b) Definition of online platform Section 301 of the Federal Election Campaign Act of 1971 ( 52 U.S.C. 30101 ) is amended by adding at the end the following: (27) Online platform (A) In general The term online platform means any public-facing website, web application, or digital application (including a social network, ad network, or search engine) that— (i) (I) sells qualified political advertisements; and (II) has 50,000,000 or more unique monthly United States visitors or users for a majority of months during the preceding 12 months; or (ii) is a third-party advertising vendor that has 50,000,000 or more unique monthly United States visitors in the aggregate on any advertisement space that it has sold or bought for a majority of months during the preceding 12 months, as measured by an independent digital ratings service accredited by the Media Ratings Council (or its successor). (B) Qualified political advertisement For purposes of this paragraph, the term qualified political advertisement means any advertisement (including search engine marketing, display advertisements, video advertisements, native advertisements, and sponsorships) that— (i) is made by or on behalf of a candidate; or (ii) communicates a message relating to any political matter of national importance, including— (I) a candidate; (II) any election to Federal office