[stoppingdown]

It's not so easy, fortunately. While they are not so spread, there's quite a number of open software (dcraw, libopenraw) used by some commercial product, and they haven't been suited so far, in spite of being able to deal with virtually every camera model in the world. Reverse-engineering, if done with the purpose of interoperability, is decently warranted by law (furthermore, we're not talking of reverse-engineering a piece of software, but a datum; software might be protected by a license agreement which usually forbids reverse engineering, but the raw file is mine and not protected by the license).

 

Even though the scenario is in constant evolution, sometimes towards the good, others towards the bad. And, of course, with some gray areas.

 

Sure, the "only the original converter..." point is valid, but, then, everybody would pick the proper solution for his need.