Allow States and Victims to Fight Online Sex Trafficking Act (FOSTA)

New exception to intermediaries' immunities under CDA 230
Document type

The Allow States and Victims to Fight Online Sex Trafficking Act is the first amendment since 1996 to one of the US’s core Internet laws, Communications Decency Act Section 230 (CDA 230). (The bill is commonly referred to as FOSTA, based a title from an earlier draft, and was also at one point known as SESTA.)  CDA 230 broadly immunizes intermediaries from liability for content posted by users, with the important exceptions of intellectual property claims and federal criminal claims. FOSTA adds a new exception for claims involving prostitution and sex trafficking.

FOSTA amends CDA 230 itself, and also amends existing federal criminal laws covering prostitution (18 USC 2421A) and trafficking (18 USC 1591 and 1595). It exposes intermediaries to two new categories of lawsuits. One is civil claims brought by private parties under federal law. The other is criminal claims brought by state officials. State attorneys general may now bring criminal prosecutions under state laws, if they target content that would violate FOSTA’s federal prostitution and trafficking provisions.

Liability for intermediaries under SESTA turns in important part on mental state or scienter. For most aspects of the law, a plaintiff or prosecutor must show “knowledge,” but for some situations liability may instead be premised on “reckless disregard.” Numerous critics of the bill, including advocates for start-ups, argued that the standard was confusing, leaving intermediaries with very little certainty about their legal obligations, and with great incentive to err on the side of taking down both lawful and unlawful content.

Eric Goldman’s blog closely tracked the law’s development. It will remain an important source for related developments such as criminal prosecutions against Backpage (which pre-dated FOSTA’s enactment, indicating that DOJ already had power to prosecute the platform under existing law) and the closure of general purpose services such as the Craigslist personals ads section.

In a CIS White Paper, Intermediary Liability Director Daphne Keller argued that FOSTA would be better tailored to serve its purpose if it

  • better defined the kinds of “knowledge” that could trigger liability
  • provided notice and takedown procedural protections modeled on the Manila Principles or portions of the DMCA
  • Specified that intermediaries have no legal duty to monitor usergenerated content
  • More clearly preserved the CDA’s “good Samaritan” clause (47 USC 230(c)(2)), so that OSPs do not face legal disincentives to weed out bad content
  • Excluded technical infrastructure providers like ISPs from its requirements, permitting them to operate as de facto common carriers
  • Encouraged or required, public transparency from both OSPs and government agencies involved in noticeand-takedown


Topic, claim, or defense
Child Protection (Includes Child Pornography)
Physical Harm (e.g. Assault, Trespass to Chattels)
Document type
Issuing entity
Legislative Branch
Type of service provider
General or Non-Specified
Issues addressed
Trigger for OSP obligations
OSP obligation considered
Block or Remove
Type of liability
Type of law
General effect on immunity
Weakens Immunity
General intermediary liability model
Takedown/Act Upon Knowledge (Includes Notice and Takedown)