Apple Inc earned gross margins of 49 to 58 percent on its U.S. iPhone sales between April 2010 and the end of March 2012, while gross margins on the iPad were much lower during much of that period, according to a court filing.

The information was revealed on Thursday in a freshly unsealed statement from an Apple expert witness, filed in the company's patent battle against Samsung Electronics Co Ltd.

An Apple representative declined to comment on the court filing.

Between October 2010 and the end of March 2012, Apple had gross margins of 23 to 32 percent on its U.S. iPad sales, which generated revenue of more than $13 billion for Apple, the filing said. Apple does not typically disclose profit margins on individual products.

U.S. iPhone sales between April 2010 and the end of March 2012 generated revenue of more than $33 billion for Apple.

Apple and Samsung, the world's largest consumer electronics corporations, are waging legal war around the world, accusing each other of patent violations as they vie for supremacy in a fast-growing market for mobile devices.

A trial is scheduled to begin in federal court in San Jose, California, on Monday. Apple is seeking roughly $2.53 billion in damages, plus permanent injunctions on some Samsung phones and tablets.

The case in U.S. District Court, Northern District of California, is Apple Inc v. Samsung Electronics Co Ltd et al, 11-1846.