Eh... isn't the Joint Photographic Experts Group the one that patents everything?
Individual companies within a certain jurisdiction can certainly set up pools and court the various rightsholders who participate in the standards process, and that is what you see with e.g. MPEG-LA and HEVC Advance in the US. But these have no direct connection to ISO beyond using the name and serving the contributing organizations.
Also, JPEG and MPEG are both part of the same standards group. And Divx is just a brand of MPEG implementations.
Sadly I can't edit my top post any more :/
The only thing to blame standard bodies for is their dysfunctional approach at patents that incentivizes useless feature stuffing so that all parties have some patents in the mandatory-to-implement part of the spec.