The end of the JPEG patent - sort of [LWN.net]

Forgent Networks is a company which would easily qualify as a patent troll for many observers. This small company picked up a data compression patent in 1997, and has been busily using that patent to shake down corporations ever since. Since this patent is said to cover the JPEG image format, there is a wide list of possible victims to choose from. Those victims have dropped more that $100 million into Forgent's bank account, and Forgent currently has litigation outstanding with some 30 companies.

The Public Patent Foundation chose this patent as one which was vulnerable to a challenge. The Foundation's work bore fruit on May 25, when the US Patent Office issued a ruling on the Forgent patent [PDF]. The resulting press release from the Public Patent Foundation was triumphant:

"The Patent Office has agreed with our conclusion that it would have never granted Forgent Networks' '672 patent had it been aware of the prior art that we uncovered and submitted to them," said Dan Ravicher, PUBPAT's Executive Director.

It is worth noting that Forgent had a different spin on the ruling:

...the United States Patent and Trademark Office issued its first office action, a non-final action, confirming a majority of the claims in United States Patent 4,698,672. The action upholds 27 of the 46 claims of Forgent's patent. Forgent will vigorously defend the remaining claims that were not initially upheld in this first office action.

Anybody wondering if the world is now safe for JPEG users will clearly need to look beyond the press releases and dig into the patent and the USPTO ruling directly. The short story is that, while the independent claims of U.S. Patent 4,698,672 have been invalidated, many of the more-specific dependent claims remain standing. Consider, for example, claim 1:

A method for processing digital signals, where the digital signals have first values, second values and other values, to reduce the amount of data utilized to represent the digital signals and to form statistically coded signals such that the more frequently occurring values of digital signals are represented by shorter code lengths and the less frequently occurring values of digital signals are represented by longer code lengths, comprising,

forming first runlength code values representing the number of consecutive first values of said digital signals followed by said second value,
forming second runlength code values representing the number of consecutive first values of said digital signals followed by one of said other values.

What the Public Patent Foundation asserted is that this claim - covering a fairly basic run-length encoding scheme - had already been claimed by another patent: #4,541,012 by Andrew Tescher. The Patent Office agreed, and ruled that claim 1 was invalid.

The story does not stop there, however. There are a number of dependent claims which make claim 1 more specific; these include:

2. The method of claim 1 further including the step of amplitude encoding said other values.

3. The method of claim 1 further including the step of encoding said first and second runlength code values with a sign value.

4. The method of claim 1 wherein said first values have amplitude zero, said second values have absolute amplitude one, and said other values have absolute amplitudes greater than one whereby said first and second runlength codes values are formed representing the number of consecutive zeros.

5. The method of claim 1 wherein said first values have the highest frequency of occurrence in said digital signals, wherein said second values have the next highest frequency of occurrence in said digital signals, and wherein said other values have the lowest frequency of occurrence in said digital signals.

Claim 3 (adding a sign value) was also rejected, but claims 2, 4, and 5 were upheld by the Patent Office. The same pattern persists through the remaining claims: the independent claims were rejected, but the more-specific versions were allowed. That is why Forgent proclaims that the majority of its claims had been upheld.

So, to a great extent, the Forgent patent survives, having lost only the most general of its claims. We asked Dan Ravicher of the Public Patent Foundation whether this ruling was enough to remove the threat against JPEG users; his response was:

It likely won't be enough to put an absolute end, but this is a significant blow to the solitary patent that are using against the JPEG standard. To the extent we've shown their armor to be made more of tin or paper, than steel or iron, we've provided the public the benefit of a more transparent view of the legitimacy of their claims.

Whether the remaining claims in the patent are applicable to the JPEG standard is a matter for the courts to determine - and, given the thirty-some outstanding cases, the courts will certainly have the opportunity to do so.

There is one interesting additional factor which, thanks to the Public Patent Foundation's work, may just come into play here. Forgent's patent was originally filed from a company called Compression Labs, Inc. It turns out that the Tescher patent, which provided the prior art used against Forgent's patent, was also developed at Compression Labs. In other words, when Compression Labs filed for the patent now being wielded by Forgent, it must have known about the existence of the prior art, since it had patented that prior art itself. But Compression Labs did not disclose that prior art to the Patent Office. Failure to disclose known prior art is a violation of the Patent Office rules. It seems likely that defendants in Forgent's litigation will find a way to let their respective courts know that the patent at issue was obtained in bad faith.

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The end of the JPEG patent - sort of

Posted Jun 1, 2006 13:12 UTC (Thu) by bangert (subscriber, #28342) [Link]

which afterall is a good thing - it gives the big players an incentive to fight instead of
just paying their way out.

Give the ill-gotten patent profits back

Posted Jun 2, 2006 13:18 UTC (Fri) by jstAusr (guest, #27224) [Link]

Big players like nothing more than crushing their opponents, the ability to cause more damage would be an incentive. The lawyers would love to retry the old cases because it would be a new revenue stream. Maybe more importantly, it would cause the patent holders to be more careful about insuring that their patents were actually valid. Of coarse, no software patents would be a better solution but, putting pressure on ill-gotten profits would be helpful.

Give the ill-gotten patent profits back

Posted Jun 2, 2006 20:34 UTC (Fri) by allesfresser (subscriber, #216) [Link]

Indeed, that's the whole point, since ill-gotten profits are the whole reason this unhappy and sordid business came to be in the first place. If somehow we can make the chances of making money out of such a scheme low enough, it will stop happening. The trick is to figure out how to do this. :-(