Comment by inigyou
2 days ago
Has it been proven that no patent troll holds a patent covering RISC-V?
Of course not because that's impossible to prove.
2 days ago
Has it been proven that no patent troll holds a patent covering RISC-V?
Of course not because that's impossible to prove.
If you iterate trough every concept RISC-V has, you might be able to prove it.
The RISC/MIPS concepts date back over 40 years. The base instruction set is intentionally designed with unencumbered, expired, or public-domain architectural concepts.
RICV-V microarchitectures and implementations are at much high risk of violating patents. Especially anything that is even slightly high performance. SiFive, Andes , and Alibaba’s T-Head are filing thousands of patents on microarchitectural optimizations and extensions. China's RISC-V patent-sharing alliances and other industry groups are building defensive patent cross-license around their RISC-V-related patents.
Patents only last 20 years.
If you build your architecture on ideas that are documented to be older than twenty years, it greatly reduces the risk that a patent holder comes from nowhere: even if they did have the patent, it would have expired.
How quickly does the industry move? Would there be any value in a 2006-era instruction set? How would you even start making sure you didn’t infringe on any patents that came after 2006?
The first version of RISC-V was released in 2010. It was based on work done at Berkeley in the 1980s (RISC versions one to four).
One reason that RISC-V has so many optional extensions is that you can trust the core is very likely to be patent-free (because everything in it is documented to be older than 20 years) and just evaluate the extensions you need.
You might find this relevant: RISC-V Genealogy (2016) https://riscv.org/wp-content/uploads/2025/02/EECS-2016-6.pdf
Or in poster form: https://riscv.org/wp-content/uploads/2025/02/RISC-V-Instruct...
Yeah, very much legally distinct MIPS, at least as a starting point.
The biggest tell is the mnemonics. While RISC-V takes a bunch of ideas from other places, and cleans things up, it copies a lot of mnemonics straight from MIPS.
But it also copies a lot of other ideas from MIPS, like the absolute distain for flag registers.
>absolute distain for flag registers
It's worst aspect maybe.
9 replies →
> Of course not because that's impossible to prove.
Why?
It's supposed to be impossible to prove a negative. But it might still happen some day. We just don't know.
"it's impossible to prove a negative" is a simplification. A negation is just the oppositive of an affirmation. If the affirmation is "there is an element E of an infinite set S that satisfies property P", the negation would be "there is no E in S that satisfy P", which would make proving by enumeration require checking every element of an infinite set, which is impossible. But other forms of proof might be possible.
The set of US patents, however, are not infinite and, IIRC, is also public. That said, IP laws are a mess.
3 replies →
Well played