After so many years that idea should be laughed at at court. Patents are one thing but waiting for your "free" codec to gain usage across the world only then to reap the benefits should be called fraud.
It’s also just a sign of how broken the system is. These companies didn’t contribute anything to the creation of opus. The codec would have still existed since it was designed explicitly to avoid existing patents.
Unfortunately I don't know of any legal theory that would actually cause a judge to rule this as fraud. Unlike trademarks for instance, there's no requirement for you to actively defend a patent to have it be valid.
Estoppel. The development process was highly publicized and the relevant entities surely knew about the call for patent claims.
And possibly laches. Patents are highly dependent on the technological context of when they're written. The Opus development process deliberately sought to avoid existing patents, and trying to reverse these judgements a decade later is disingenuous.
