Jan 19 (Reuters) - If you hadn't heard of the House of Representatives' Stop Online Piracy Act or the Senate's corresponding Protect I.P. Act before Wednesday, you surely have now, after Wikipedia, Craigslist, and many other Internet information providers went dark in protest of the pending legislation. SOPA and PIPA, as the bills are known, are being pushed by movie studios, publishers, and other copyright holders who want to curb online piracy by overseas websites. But lots of U.S. Internet companies contend that SOPA and PIPA undermine the safe-harbor provisions of the Digital Millennium Copyright Act, which protects websites that inadvertently publish copyrighted material.

Among the sites that turned off the lights Wednesday was Stanford Law School's Center for Internet and Society. In a note to followers, the Center's executive director, Anthony Falzone, explained that even as support for SOPA dries up, PIPA still seems to be alive and well, with "dangerous" provisions that "threaten both the universality and the security of the Internet itself."

It's more than a little ironic that on a day the Center's site was protesting Congress's perceived encroachment on free speech, the U.S. Supreme Court issued a decision that rejected CIS's argument in a case challenging Congress's power to restrict what's in the public domain. Even worse for opponents of Congress's anti-piracy legislation, the Court's opinion in Golan v. Holder expressly endorses Congressional authority to determine the scope of copyright protection. If some version of SOPA or PIPA is enacted, in other words, it will be tough to overturn in the courts.

The Golan backstory is fascinating. As the Court's review of the history of copyright law explains, the United States was once a notorious copyright violator. Until the 1890s, this country offered no copyrights to foreign authors, so publishers regularly put out U.S. editions of their work without paying for the rights. According to the Golan opinion, the senator who championed an 1891 law to extend copyright protection to overseas authors said the U.S. was "the Barbary coast of literature" and its people "the buccaneers of books."

More than a hundred years after the international Berne Convention for the Protection of Literary and Artistic Works took effect in 1886, the United States finally agreed to join. That meant foreign authors would get the same protection as U.S. rightholders in this country, and that U.S. authors' rights would receive reciprocal recognition overseas. But Congress didn't initially extend Berne rights retroactively, so music, films, and literature that had already entered the public domain in the United States remained public, even if it was still copyrighted abroad.

Some countries in the Berne convention objected to that policy -- and threatened to restrict U.S. copyrights on their turf in retaliation. In response to calls from U.S. copyright holders, Congress reversed course and passed a new law in 1994 that effectively took a vast number of recordings, films, and books out of the public domain. (The list includes Sergei Prokofiev's Classical Symphony and Peter and the Wolf; Dmitri Shostakovich's Symphony 14, and Igor Stravinsky's Petrushka.)

A group of orchestra conductors, film archivists, movie distributors, and educators sued to overturn the 1994 law. As their case made two trips through the trial court and U.S. Court of Appeals for the Tenth Circuit, their chances dimmed: The Supreme Court, in 2003's Eldred v. Ashcroft, upheld Congress's Constitutional right to extend the length of copyright protection. But the Golan plaintiffs claimed that even after Eldred , the Constitution's Copyright Clause did not give Congress the power to take works out of the public domain, and even if it did, the First Amendment's protection of free speech trumps any law that extends retroactive protection to works that are already public. (Here's the Supreme Court brief filed by the Center for Internet and Society and its co-counsel; the voluminous amici briefing on both sides is here.)

In an opinion written by Justice Ruth Bader Ginsburg, a majority of the Court disagreed. "Nothing in the historical record, subsequent congressional practice, or this Court's jurisprudence warrants exceptional First Amendment solicitude for copyrighted works that were once in the public domain," the opinion said. "[The 1994 law] simply placed foreign works in the position they would have occupied if the current copyright regime had been in effect when those works were created and first published."

Falzone of the Center for Internet and Society told me Thursday that the Court's ruling "is a continuation of the trend in Eldred, in which the Court shows a great deal of deference to Congress's decisions about the scope of copyright and IP laws." I asked if that's bad news for opponents of the proposed anti-piracy legislation. Falzone's answer: "One of the lessons of Golan is, 'Don't wait.' You have to stop the legislation before it gets passed. You have to stop it in its tracks before it gets to the courts."

And as disappointing as the Golan ruling was, Falzone said he was encouraged by the popular uprising against SOPA and PIPA. In the wake of Wednesday's blackout, he said, legislative support for the bills is waning.

(Reporting by Alison Frankel)