[lmc]

This is on their website...

"Is Kimi K2.5 open source?"

"Yes, Kimi K2.5 is an open source AI model. Developers and researchers can explore its architecture, build new solutions, and experiment openly. Model weights and code are publicly available on Hugging Face and the official GitHub repository."

https://www.kimi.com/ai-models/kimi-k2-5

[saidmukhamad]

4th paragraph in license block

Our only modification part is that, if the Software (or any derivative works thereof) is used for any of your commercial products or services that have more than 100 million monthly active users, or more than 20 million US dollars (or equivalent in other currencies) in monthly revenue, you shall prominently display "Kimi K2.5" on the user interface of such product or service.

[ffsm8]

My first reaction was "well, who knows how much revenue they're actually doing"

But at least the rumor mill has them significantly above that line:

> Revenue: As of March 2026, reports suggest Cursor has surpassed $2 billion in annualized revenue (ARR).

[lmc]

That's not an open source license, then.

[bakugo]

It wouldn't be regardless, because the model is open weights, not open source. It's just a license.

[lmc]

Which contradicts what they say on their website.

[igravious]

Correct. (and I know you already know this but just for the record: (Nearly?) Everybody abuses the term "open source" when it comes to models. OSI have a post about it: https://opensource.org/ai/open-weights

[ZeroAurora]

Although it is not OSI approved, the license theoretically didn't add any more restrictions beyond attribution, which stays in line with The Open Source Definition.

[lmc]

That's debateable. How about, e.g, "10. No provision of the license may be predicated on any [...] style of interface."

Anyway, if it was clear cut, it shouldn't be difficult to get it approved.

These kinds of discussions show why it's a pain to use non standard licenses.

[kbrkbr]

Why not?

[lmc]

This 'Modified MIT' is not a license that has been through the OSI process: https://en.wikipedia.org/wiki/The_Open_Source_Definition#Com...

You can't just add random terms to an existing license and use its name. "Modified MIT: Like MIT but pay us 50 million dollars."

Perhaps CC-BY would've been more appropriate.

[igravious]

Correct again -- CC- applies to data, not code -- weights are data, open weights suggests a creative commons approach …

“ CC-BY 4.0 Creative Commons Attribution 4.0 International

This license requires that reusers give credit to the creator. It allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, even for commercial purposes.

BY Credit must be given to you, the creator. ”

it's annoying the open source term is being cargo-culted around and I hate to say it but that ship looks like it has sailed.

funny that free software people were infuriated by the open source term and now the open source term is being completely misused in another context

[tempaccount420]

Ah yes, a document titled "*THE* Open Source Definition", describing *THEIR* definition of open source.

[array_key_first]

Their definition matters more than most, I mean, anyone can define anything however they like. Hell, Windows is open-source, because I said so.

Also, even if it were not for the OSI, this still wouldn't be open source. Because there's no source code available. It's open-weight, which is a different thing. The models weights are, essentially, the "compiled" output. The input and algorithms, we don't know.

[Eridrus]

Cursor have said they are using Composer through their inference provider (Fireworks). Presumably the MIT is not viral like the GPL, so Cursor, and companies that use Cursor do not need to display Kimi attribution on their products.

It's definitely not what Kimi wanted, but it sounds like this is what is written.