Preliminary injunctions against libel, obscenity, and other kinds of speech are generally considered unconstitutional prior restraints. Even though libel may inflict truly irreparable harm on its victim, the most a libel plaintiff can hope for is damages, or perhaps a permanent injunction after final adjudication, not preliminary relief. Professors Lemley and Volokh argue the same rule should apply to preliminary injunctions in many copyright, trademark, right of publicity, and trade secret cases. They note that intellectual property rights, unlike other property rights, are a form of content-based, government-imposed speech restriction. The mere fact that the restriction is denominated a "property right" should not exempt it from conventional First Amendment scrutiny, or justify government action that restricts speech which ultimately proves to be constitutionally protected. This is especially so because in most cases, damages would be a relatively effective remedy. The Court's prior restraint doctrine and sound First Amendment policy suggest that preliminary injunctions in intellectual property cases are often (though not always) unconstitutional.
Mark A. Lemley & Eugene Volokh,
Freedom of Speech and Injunctions in Intellectual Property Cases,
48 Duke Law Journal
Available at: http://scholarship.law.duke.edu/dlj/vol48/iss2/1