Disincentivizing Internet Service Censorship of Online Users and Restrictions on Speech and Expression Act or the DISCOURSE Act This bill limits federal liability protections for a user or provider of an interactive computer service (e.g., a social media company) related to content provided by third parties. It also requires a provider that offers its service through a mass-market offering to the public to disclose information about its content moderation activities. The bill removes liability protections (sometimes referred to as section 230 protection) for a provider with a dominant market share if the provider promotes or suppresses a viewpoint through its content moderation, including by affecting a content creator's revenue; uses automated processes (e.g., algorithms) to target and amplify content provided to a user who has not requested or searched for the content; or solicits, funds, modifies, or otherwise contributes to content. Currently, a provider retains liability protections even when it restricts access to materials that it considers objectionable. Under this bill, a provider retains protections if restricted materials fall, based on an objectively reasonable belief, into a prescribed list of harmful or unlawful categories. Additionally, the liability protections shall not apply to providers that (1) restrict access to content in a manner that burdens the exercise of religion, or (2) fail to comply with an existing requirement to notify customers of options for limiting a minor's access to harmful online content (e.g., parental controls). The bill also changes legal procedures related to the liability protections, including by specifying that the protection serves as an affirmative defense.