Thanks for the information.

1) According to that link the VP8 patents are licensed for use in VP9 (which I had forgotten or didn't know) but there is still the possibility of new patent from existing licensees in addition to additional patent holders coming forwards.

3) The reference you give is to one of the patents but there are more than one involved. As far as I know it is still an ongoing open issue.

as for 1), it's also possible that there are h.264 patents that aren't part of the pool.

Thomson created what is essentially an MP3 license pool, and yet, Sisvel cleaned out Cebit (one of the larger electronics fairs) booths every year (with the help of German customs) because some asian vendors showed unlicensed MP3 players.

It's still possible that some non-MPEGLA party stumbles over a patent that covers some tiny aspect of h.264.

Its possible but it is now improbable that there are strong critical patents in H.264 which aren't either in the pool or at least owned by a company that participated in the standards setting (and are therefore bound by FRAND commitments). The reason I believe it improbable is that anyone in that position has hit the jackpot and are entitled to fees related to virtually every phone, television and blu-ray player currently being produced - there is no reason to wait further they can cash in now.

VP8 has not been widely deployed (at least in hardware) to anything like the same extent so the possibility of lurkers is greater.

Getting products pulled from Cebit (and German Customs helping) is for me a completely wrong on so many levels I can barely describe (at least if the products weren't for sale to the public).