The U.S. Supreme Court on Monday rejected an appeal by digital media manufacturers who are battling a patent-infringement lawsuit filed by flash-data storage-card maker SanDisk Corp. (SNDK).

The court denied manufacturers Ritek Corp., Memorex Products Inc. and Pretec Electronics Corp.'s petition aimed at reversing a July federal appeals court ruling that reinstated SanDisk's infringement suit.

The appeals court overturned a decision by a federal judge in California, who had granted motions to dismiss the case at different times in 2003 and 2004.

At issue are flash memory devices used in products such as digital cameras, personal digital assistants and MP3 players.

Ritek is a manufacturer of the flash memory devices. Pretec is a subsidiary of a privately owned Taiwanese manufacturer, while Memorex was a distributor.

In October 2001, SanDisk sued the three companies, saying they had infringed on a patent on flash memory technology.

A fourth company originally named in the suit, Power Quotient International Co., reached a settlement with SanDisk earlier.

The California judge overseeing the case, U.S. District Judge Vaughn Walker, granted motions by Ritek, Pretec and Memorex to dismiss the case in 2003 and 2004.

However, the appeals court ruled Walker had misconstrued the patent at issue and sent it back to him for further proceedings.