If you open the text and look at section 2 of bill S.2658, you will see the definition of "Large Communications Platform Providers": (7) LARGE COMMUNICATION

If you open the text and look at section 2 of bill S.2658, you will see the definition of "Large Communications Platform Providers": (7) LARGE COMMUNICATIONS PLATFORM.—The term “large communications platform” means a product or service provided by a communications provider that— (A) generates income, directly or indirectly, from the collection, processing, sale, or sharing of user data; and (B) has more than 100,000,000 monthly active users in the United States.