Studios are rushing to make new variations on “Snow White” and “The Wizard of Oz,” which are instantly recognizable titles and, even better, are not under copyright. But the industry is not lining up behind a legal argument that is coming before the Supreme Court next week: once in the public domain, always in the public domain.

Far from seeing the case of Golan vs. Holder as a matter of free speech, the studio and recording industry lobbies see it as having ramifications in the overseas protection of copyrighted movies, TV shows and music.

A group of orchestra conductors, educators and homevid distributors are among those challenging the constitutionality of a 1994 act of Congress that restored the copyrights of perhaps millions of foreign works that had fallen into the public domain.

The law was part of the Uruguay Round Agreements Act of 1994, and the rationale was very simple: If the U.S. restored copyrights of works from other countries, those countries would do the same for titles that had fallen into the public domain. Supporters of the act say it was needed to honor treaty obligations and bring the U.S. in compliance with the Berne Convention, the international agreement in which countries recognize other the copyright of works from other signatory countries,

But the plaintiffs in the case, such as conductor Lawrence Golan, say the law removed works from the public domain, like Prokofiev’s “Peter and the Wolf” and Shostakovich’s Symphony No. 14, that were critical to their professions. According to the U.S. Copyright Office, in the years following the passage of the law, some 48,505 notices of intent to enforce copyrights were filed for works believed to have fallen into the public domain, including not just music works but a large number of Mexican and Latin American films, Alfred Hitchcock titles like “The 39 Steps” and “The Lady Vanishes” and Carol Reed classic “The Third Man.”

The plaintiffs argue that the case is far from esoteric and concerns the boundary between copyright and free speech. As they said in their brief to the Supreme Court, they “lost important speech and expression rights central to their professions, as well as the expected return on significant investments.”

They argue that the law violates the limited-time restriction of the copyright clause of the Constitution and that the “entry of a work into the public domain must mark the end of protection, not an intermission. Otherwise, the limit is meaningless.” And they say that it marks a violation of the First Amendment as it “eliminated the speech and expression rights central to their professions, and expropriated the investment they made.”

Last year, the 10th Circuit Court of Appeals said that the law survived First Amendment scrutiny because it was narrowly tailored and advanced government’s interest in protecting the works of U.S. authors in other countries. That’s why the high court’s March decision to take the case triggered so much speculation as to whether it was really looking to overturn the law or to consider the relationship of copyright law and the First Amendment.

If the high court does overturn the law, “It could hurt the protection of U.S. films and music abroad because some U.S. trading partners may say, ‘Well, if the U.S. is not fully abiding by the obligations of copyright treaties, why should we do so?” said Eric J. Schwartz, partner in the Washington office of Mitchell, Silberberg and Knupp, who was acting general counsel of the U.S. Copyright Office when the 1994 law was passed.

Among those filing amicus briefs was the MPAA, which warned that U.S. copyright holders could be subject to “retaliatory measures” in other countries if the U.S. does not honor the treaty. (Reed Elsevier, parent company of Variety, has also filed an amicus brief in favor of the government’s case.)

Rather than being a case about free speech, the MPAA suggests, it is “solely about a narrowly defined class of foreign works that prematurely fell into the public domain due to rigid copyright formalities.” The reason wasn’t that the copyright term ended but often that an owner in another country didn’t file an extension or even had the means to do so.

They note that the new law doesn’t alter the ability of libraries and archives to use the material, along with church groups and other organizations. And it also didn’t change the doctrine of fair use, in which copyrighted material can be used in a limited amount without the owner’s consent.

The plaintiffs question whether the law’s reach was necessary to comply with the treaty and have argued that the government had “no legitimate interest in giving away public speech rights in the hope of creating private economic windfalls.”

The works at hand may not be the basis for the next studio tentpole, but as with so many Supreme Court matters, the decision may have an impact well beyond those who’ll be watching next week with interest.