Platform and Marketplace Compliance · Memo

Section 230 Limits for Content-Moderating Marketplaces

Section 230 protects marketplaces less than the marketing copy suggests. I will walk through the doctrinal lines, the recent Ninth Circuit case law, and the conduct that falls outside the safe harbor.

47 U.S.C. section 230(c)(1) provides that no provider or user of an interactive computer service shall be treated as the publisher or speaker of any information provided by another information content provider. Section 230(c)(2) provides a related but distinct protection for good-faith content moderation. Together, the provisions are the structural protection that allowed the modern internet to develop. They are also, in 2026, more limited than they were in 2018, and the limitations are particularly relevant to marketplaces that moderate or rank seller content.

The doctrinal architecture

Section 230(c)(1) protects the platform from being held liable as a publisher of user content. Defamation, certain torts, and statutory claims that depend on publisher status fall within the protection. The limits, as developed in the case law:

• Federal criminal law. Section 230(e)(1) excludes federal criminal law from the safe harbor.
• Intellectual property. Section 230(e)(2) excludes intellectual property law from the safe harbor.
• Electronic Communications Privacy Act. Section 230(e)(4) excludes ECPA-related claims.
• Sex trafficking law. Section 230(e)(5), added by FOSTA/SESTA in 2018, excludes certain sex-trafficking-related claims.
• The platform's own conduct. The safe harbor does not extend to a platform's own conduct (creating content, materially contributing to content) as opposed to merely hosting or displaying third-party content. Fair Housing Council v. Roommates.Com, 521 F.3d 1157 (9th Cir. 2008), is the foundational case.

What Roommates.com established

The Ninth Circuit's en banc decision in Roommates held that a platform loses Section 230 protection for content it has materially contributed to. The roommate-matching site's required user responses to certain questions (gender, sexual orientation) and its filtering of results based on those responses made the site responsible as a content creator, not merely a platform displaying user-generated content.

The Roommates framework has been applied unevenly in subsequent cases. The Ninth Circuit's 2024 decisions have tightened the protection in certain contexts. The Lemmon v. Snap Inc. line, the Ninth Circuit's 2024 decision in Doe v. Twitter, and the related matters have signaled that platforms whose features (algorithmic amplification, design choices, structured-input forms) materially contribute to harmful content cannot rely on Section 230 to immunize the resulting harm.

The marketplace context

For marketplaces, the most-relevant Section 230 questions involve:

1. Liability for seller content. Listings, descriptions, photos, and other content posted by sellers are third-party content. The marketplace's display of that content is generally protected. The protection narrows if the marketplace materially contributes to the content (e.g., translating it inaccurately, modifying descriptions, adding ranking based on contested categories).
2. Liability for marketplace recommendations. Algorithmic ranking and recommendation engines have been treated inconsistently. The Force v. Facebook line and similar cases have held that recommendations are within Section 230 protection in many contexts. The Ninth Circuit's 2024 decisions have raised questions about whether algorithmic amplification of harmful content is materially contributory.
3. Liability for moderation decisions. Section 230(c)(2) protects good-faith moderation decisions. The 'good faith' standard has not been heavily litigated, but bad-faith or pretextual moderation has been treated as outside the protection.
4. Liability for marketplace-specific procedures. Procedures that require sellers to provide structured information, that filter listings based on platform criteria, or that translate or modify listings for display can move the marketplace closer to the Roommates line.

The IP and FOSTA/SESTA carve-outs

For marketplaces selling physical goods, the intellectual-property carve-out at section 230(e)(2) is the most significant limit. Trademark and copyright claims are not within Section 230's protection. The DMCA at 17 U.S.C. section 512 provides a separate safe harbor for copyright infringement claims, conditional on the platform's compliance with takedown procedures. The Lanham Act provides no similar safe harbor for trademark, leaving marketplaces exposed to contributory and vicarious trademark liability under the Tiffany v. eBay framework (2d Cir. 2010) and its progeny.

FOSTA/SESTA's carve-out at section 230(e)(5) excludes from Section 230 protection the violation of federal criminal sex-trafficking statutes and the related state-law claims. Marketplaces that allow content the federal trafficking statutes prohibit cannot rely on Section 230. The carve-out's reach has been the subject of meaningful litigation; counsel should track the developing case law.

The state-law overlay

Section 230 preempts inconsistent state law. The preemption is broad but not unlimited. State criminal law that runs parallel to federal criminal law may be within preemption. State law that targets the platform's own conduct, as opposed to its hosting of user content, may not be. The lines are not always clear and the case law is jurisdiction-specific.

California's AB 587 (the social-media-platform transparency law, signed in 2022 and litigated in subsequent years) and similar state legislation have prompted court challenges on First Amendment and Section 230 preemption grounds. The doctrinal landscape on state-law platform regulation is in motion. Counsel advising a platform on state-law exposure should not assume Section 230's prior reach controls.

The conduct-based versus content-based distinction

One useful drafting and litigation distinction. Claims that target the platform for hosting or displaying user content are typically within Section 230 protection. Claims that target the platform's own conduct (its design choices, its data-collection practices, its algorithmic decisions, its operational arrangements with sellers) are typically outside Section 230 protection.

For marketplaces, this means:

• A claim for defamation arising from a seller's product description is within Section 230 protection.
• A claim for unfair competition arising from the marketplace's seller-ranking algorithm may not be within Section 230 protection if the claim is framed as targeting the marketplace's conduct rather than the underlying seller content.
• A claim for tortious interference with the seller's customer relationships is conduct-based and typically outside Section 230 protection.
• A claim for breach of the seller agreement is contract-based and entirely outside Section 230 protection. Section 230 does not preempt contract claims.

The Moody and NetChoice cases

The Supreme Court's 2024 decisions in Moody v. NetChoice and NetChoice v. Paxton addressed the constitutionality of state social-media-platform regulations. The decisions did not directly address Section 230's reach but provided some signaling on the Court's view of platform First Amendment rights. Counsel relying on Section 230 should follow the related constitutional doctrine, because the two are increasingly intertwined.

The drafting implications for platforms

For counsel advising a marketplace on its risk posture, the operational moves that preserve Section 230 protection:

• Avoid materially modifying user content. Display it as submitted, with limited editorial intervention.
• Where moderation is necessary, document the good-faith basis for each moderation decision. Section 230(c)(2)'s good-faith standard is the safety net.
• Avoid structured-input forms that require users to make categorical choices the marketplace then uses to filter or rank. The Roommates pattern is the textbook example of conduct that loses the protection.
• Document the algorithmic-design choices in a way that the choices can be defended as content-neutral or content-aware in ways consistent with the platform's stated policies.
• Maintain separate analyses for IP, FOSTA/SESTA, and other carve-out categories. Section 230 does not protect those areas and the operational compliance must be independent.

What I would not assume

Section 230 doctrine is moving. The 2024-2025 Ninth Circuit decisions and the related cases in other circuits are tightening the analysis in ways that prior practice did not anticipate. Counsel advising a platform on its Section 230 reliance should not treat the 2018 case law as controlling. The doctrinal landscape will continue to develop, and platforms whose operations depend critically on Section 230 should have a thoughtful position that does not rely solely on the safe harbor.

Sergei Tokmakov, Esq., CA Bar #279869. This memo is attorney commentary on legal questions and is not legal advice. Reading it does not create an attorney-client relationship. Past matter outcomes depend on facts and the responding party; nothing here is a prediction of result.