Software patents are probably unenforceable in most cases, at least in the US and Europe, are essentially unenforceable. The European Patent Office, very sensibly, denies software patents.

The USPTO has a strange insistence on granting them even though they aren't legally valid. Therefore, if you have a lot of money, you might file a software patent for one of four reasons:

1) You hope that the US courts might one day change their minds and start enforcing software patents.

2) You hope that you might scare people in to giving you licensing fees even though you know the patent won't be enforced.

3) You want to prevent others from scaring you in to giving them licensing fees.

4) You want to get a patent because it's impressive/looks good on your resume.

That is why all patents exist. It's ridiculously time consuming and expensive to get a utility patent for anything. I invented something at my old company 5 years ago and the patent process is still ongoing, should hopefully get awarded this year. It costs tens of thousands of dollars in legal fees and you need to actively litigate infringements if you want to keep it. 99% of patents exist just for legal bullying and the other 1% are actually novel, useful inventions.

Almost all these patents exist as a war chest and a deterrent against other companies. Everyone theoretically perpetually infringes on each other's obscure patents all the time, but there is a detente between the big players because they hold the gun to each other's heads. If you as a small guy enter the game, you're just shot.

In theory patents are also to protect smaller players (though not dirt poor), from getting their work ripped off by bigger players after demonstrating feasibility. The idea of being an "inventor" professionally only really works with patents. Software patents pushes this model to logical extremes though. I run a small startup that trains models for medical devices and the only way to get any of the large players to care about implementing improvements you make (and not rip you off) seems to be to have some patent protection. They are mostly interested in the patents as assets to prevent their competitors from acquiring. In all honesty I'm not completely convinced on software patents either but we've had to adapt.

It builds corporate value. If you end up with a portfolio of patents that someone might want to acquire, you've just created a new market for your company. Individual software patents of common quality probably don't matter.

Economically, it’s to avoid free-rider effects. This benefit largely seems alien to tech people because the industry inherently has other moats: network effects, data and code in a server instead of a product sold to consumers that competitors can easily disassemble and reverse engineer, etc.

The real truth is that's how Edison used them and they've been the primary use of patents since inception.

I don't disagree, but Mistral is hardly a "rich player" in the current AI bubble.

OpenAI, Anthropic, Google, Meta and X are each valued at a trillion or more. Mistral is valued at $20B, 50x less. Even Deepseek is several times bigger than Mistral.

They exist so you can not be forbidden to do what you invented.. but there might be unintended correlation ;)

Precisely the reason is to give breathing room for big players to invest in development of technology so they can capitalise exclusively for a period

in what world is mistral a big player?

Mistral is not a rich player in the context of AI. It is minor smaller company, basically.