The Massachusetts Institute of Technology and a California company have filed a lawsuit in East Texas, claiming that 94 firms — including Microsoft Corp. — illegally used their patented image editing software.

MIT says Electronics for Imaging Inc., of Foster City, Calif., has an exclusive license for the software, developed by MIT professor William Schreiber and used in products such as photo scanners and digital cameras. The patent expires this year.

In the suit, filed last week in a federal court near an EFI office in Texarkana, Texas, EFI demands the firms pay license fees for the past six years. A company spokesman would not say how much they fees are.

EFI won control of the patent in 1990 and has licensed it to 16 other companies, including Apple Computer Corp. and Xerox Corp. The software design firm shares its revenue with MIT.

EFI has collected between $20 million and $30 million in license fees, a spokesman told the Boston Herald, but wouldn't say how much went to MIT.

Other firms named in the suit are Polaroid Corp., International Business Machines Inc., Photoworks Inc., and ScanSoft Inc. Microsoft and Polaroid spokesmen told the Herald on Friday that they hadn't seen the suit and couldn't comment.