Many states permit a defendant to move early to strike claims arising from protected speech or petitioning activity, with fee shifting.
Two steps. The defendant shows the claim arises from protected activity — statements before a legislative, executive or judicial body, statements in connection with an issue under consideration by such a body, statements in a public forum on an issue of public interest, and in broader statutes, any conduct in furtherance of speech on a public issue. The burden then shifts to the plaintiff to establish a probability of prevailing.
Effect on discovery. Most statutes stay discovery pending the motion, with limited exceptions on a showing of good cause. That stay is the principal protection and the principal complaint.
Fees. A prevailing defendant recovers fees, mandatory in many statutes. A plaintiff prevailing against a frivolous motion may recover fees as well.
Appeal. Denials are immediately appealable in many states, which extends the case but also increases the pressure to abandon a weak claim.
Federal application to state law claims is unsettled and divides the circuits.
Commercial relevance. Claims arising from statements to regulators, consumer reviews, media statements about a dispute, and litigation-related communications are all within scope, which makes the analysis part of any decision to sue over speech.