APPLE Inc conspired with publishers to raise electronic book prices, a federal judge ruled yesterday, saying the evidence left no doubt that the computer maker broke antitrust laws.

US District Judge Denise Cote said Apple knew that no publisher could risk acting alone to try to eliminate Amazon.com's US$9.99 price for the most popular e-books so it "created a mechanism and environment that enabled them to act together in a matter of weeks to eliminate all retail price competition for their e-books."

The Manhattan judge added: "The evidence is overwhelming that Apple knew of the unlawful aims of the conspiracy and joined the conspiracy with the specific intent to help it succeed."

She said damages could be determined at a later point.

Apple spokesman Tom Neumayr said the Cupertino-based company planned to appeal.

"Apple did not conspire to fix e-book pricing and we will continue to fight against these false accusations," he said. "We've done nothing wrong."

Assistant Attorney General Bill Baer called the ruling "a victory for millions of consumers who choose to read books electronically."

He said the judge agreed with the Justice Department and 33 state attorneys general that executives at the highest levels of Apple orchestrated a conspiracy with five major publishers to raise prices.

"Through today's court decision and previous settlements with five major publishers, consumers are again benefiting from retail price competition and paying less for their e-books," he said.

Apple attorney Orin Snyder had told Cote previously that she would set a "dangerous precedent" if she decided Apple manipulated e-book prices as it entered the market in 2010.

Neumayr said Apple's introduction of the iBookstore in 2010 "gave customers more choice, injecting much needed innovation and competition into the market, breaking Amazon's monopolistic grip on the publishing industry."

The lawsuit was filed last year against Apple and major publishers.