JPEG will launch a website to collect information from standards bodies and industry groups that it hopes will form the basis of a prior art defence that the patent should not have been granted as its basis was already published and well known.

JPEG committee member Richard Clark said that although a number of academics and industry bodies may have destroyed data from the 1980s, enough should exist for the defence.

"It points to something very wrong with the patents system. This could apply to any technology 14 years after the event," he said.

The patent was issued to Forgent subsidiary Compression Labs in 1987, but the company did not appreciate its potential significance until last year. Since then it has received a 9.56m ($15m) payment from Sony for past and future use. It has also received payment from another unnamed user.

However, the JPEG committee said that its central goal has always been that the standards should be available without payment of royalty or licence fees.

Other organisations including Lucent and Phillips may also be claiming to own part of the intellectual property rights to the format.

Story by John Davies