[seldridge]

The MIPS Open ISA project was actually shut down after only a year. [^1]

POWER has technically only been "open" for a little under a year. OpenPOWER was always a thing, but this used to mean that companies could participate in the ISA development process and then pay license fees to build a chip. This changed last year when POWER went royalty-free (like RISC-V).

The real defniition of "open" is can you answer the following questions in the negative:

  - Do I need to pay someone for a license to implement the ISA?
  - Is the ISA patent-unencumbered?

RISC-V was the only game in town for a long time and thereby attracted large companies (including NVIDIA) and startups that were interested in building their own microprocessors, but didn't want to pay license fees or get sued into oblivion.

[^1]: https://www.hackster.io/news/wave-computing-closes-its-mips-...