California has a number of formal acts in law. The Uniform Single Publication Act is contained in Section 4 of the Civil Code (General Provisions), Part 1 (Remedies), Title 4, which includes Articles 3425.1 through 3425.5. This was added in 1955 by Chapter 867.
Article 3425.1 provides that Title 4 may be cited as the single uniform act of publication. Section 3425.2 requires that this law be interpreted in such a way as to achieve its objective of uniformizing the law of the states or jurisdictions that enact it.
Section 3425.3 prohibits any person from having more than one cause of action for damages for defamation or slander or invasion of privacy or any other tort based on a single publication, exhibit or statement, such as than an issue of a newspaper or book or magazine or any presentation to an audience or any broadcast on radio or television or any presentation of a motion picture. Recovery in any action shall include all damages for such tort suffered by the plaintiff in all jurisdictions.
Section 3425.4 provides that a judgment in any jurisdiction for or against the plaintiff on the merits of any action for damages based upon a single publication, exhibit, or statement as described in Section 3425.3 bars any further action for damages. -interests by the same plaintiff against the same defendant based on the same publication or exhibit or statement.
Finally, Section 3425.5 prohibits Title 4 from being retroactive to causes of action existing on its effective date.