The copyright extension law had been challenged by a group of Internet publishers and other small businesses hoping to use hundreds of thousands of books, movies and songs due to be released into the public domain before Congress passed the 20-year extension in 1998. The group challenged the constitutionality of the law and claimed that it limited free speech and harmed the creative process.
The 7-2 high court ruling in favor the extension is a victory for companies such as Disney Corporation that own familiar cultural icons -- such as original versions of the Mickey Mouse cartoon character -- that would have cost the companies millions in lost royalties had they entered the public domain.
Media conglomerate AOL Time Warner also benefits from the court's decision since well-known movies the company owns, such as "Casablanca," "The Wizard of Oz" and "Gone With the Wind," would have also entered the public domain without the extension.
With the 1998 extension, the copyright period now lasts 70 years after the death of the creator, while works owned by corporations are now protected for 95 years. Congress has extended copyright terms 11 times over the past 40 years.
Opponents say the law unfairly restricts public access to published works and other copyrighted material.
"It's like going to each shelf and taking off anything published after 1922, putting it into a locked closet, and telling readers they will have to pay money to read those, and if they want to wait 20 years they may be able to read them for free," said Eric Eldred, the lead plaintiff in the extension challenge and the head of a public Internet library, according to Northwestern University's On the Docket.
However, a majority of the justices found that the copyright extension, which was named for the late U.S. Rep. Sonny Bono (R-Calif.), was not unconstitutional.
The Constitution "gives Congress wide leeway to prescribe 'limited times' for copyright protection and allows Congress to secure the same level and duration of protection for all copyright holders, present and future," Justice Ruth Bader Ginsburg said in delivering the court's opinion.
"We find that the [extension] is a rational enactment; we are not at liberty to second-guess congressional determinations and policy judgments of this order, however debatable or arguably unwise they may be," Ginsburg explained.
Justices John Paul Stevens and Stephen Breyer disagreed with the decision of the court.
Stevens wrote that the court was "failing to protect the public interest in free access to the products of inventive and artistic genius."
Lawyers for the Bush administration had argued in favor of the extension, telling the high court that while justices may disagree with the latest extension, Congress had the constitutional authority to pass it.