I'm sick to death of these shameless dilutions (including the notion that open-weight is open-source; the OSI is totally captured at this point)
Although to be fair, Kimi contains an identical carve out.
I would, contra the OSI, not consider the model to be open-source even if the weights were under an open-source license. But that is the minimum condition under which it could be considered open-weight.
According to who? From https://en.wikipedia.org/wiki/Open_weights:
> Publishing these values allows others to download and use the model, while permission to modify, fine-tune or redistribute it depends on its license.
Those restrictions are definitely not compatible with the definition of open-source/FOSS. I think you have a much stricter view of what open-weights means than the industry.
There was an attempt to create an analogue of the OSI's Open-Source Definition that acknowledged the problems of merely releasing weights as "open-source". That project seems to have largely failed or fizzled, and "open weight" has come to be used mostly as a way of acknowledging that only the weights have been released under open-source terms.
This model of Meta's fails even that dramatically weakened standard.
This is just a series of dilutions by which giant corporations are trying (and apparently succeeding here on "hacker" news) to trade on the cachet of commitments they don't actually hold.
"Open weights" is for the most part a term that is meaningless besides being technically able to run it on your own hardware.
I don't think we have a proper term for what you are reaching for, and proper open-source models (training, training-data, etc. being fully open) are scarce.
> I don't think we have a proper term for what you are reaching for, and proper open-source models (training, training-data, etc. being fully open) are scarce.
I think you're very much right that we don't have a "brand" with either the same kind of institutional backing as terms like "open-source" and "free software" or a wealth of examples to point to.
If you want to assess the position of the U.S. Copyright Office for yourself, the relevant text can be found in the Compendium of U.S. Copyright Office Practices § 313.2, "Works That Lack Human Authorship"[2], which states:
> […] the Copyright Act protects “original works of authorship.” 17 U.S.C. § 102(a) (emphasis added). To qualify as a work of “authorship” a work must be created by a human being. See Burrow-Giles Lithographic Co., 111 U.S. at 58. Works that do not satisfy this requirement are not copyrightable.
> […] the Office will not register works produced by a machine or mere mechanical process that operates randomly or automatically without any creative input or intervention from a human author. The crucial question is “whether the ‘work’ is basically one of human authorship, with the computer [or other device] merely being an assisting instrument, or whether the traditional elements of authorship in the work (literary, artistic, or musical expression or elements of selection, arrangement, etc.) were actually conceived and executed not by man but by a machine.” U.S. COPYRIGHT OFFICE, REPORT TO THE LIBRARIAN OF CONGRESS BY THE REGISTER OF COPYRIGHTS 5 (1965).
Oh, and there's also a bit in the following Section 313.3, "Works That Do Not Constitute Copyrightable Subject Matter"[2], which explicitly excludes mathematical principles, formulas, algorithms, and equations, along with DNA sequences and other genetic or chemical compounds, regardless of whether they are produced by humans or by nature. If one takes the perspective that machine learning models are algorithms, the conclusions on copyrightability are pretty clear.
[1] https://media.cadc.uscourts.gov/opinions/docs/2025/03/23-523...
[2] https://www.copyright.gov/comp3/chap300/ch300-copyrightable-...
You may be conflating 2 things - the Muse model weights themselves, and what the models output when run. The former is prima facie the product of human authorship and hence has full protection of copyright law, the latter fits your characterization of likely not having copyright coverage. Meta can use the copyright on the model weights to dictate licensing terms. IANAL too.
Only in the way a math textbooks are facts. Model weights are bits on a medium,designed and derived from the combined efforts, judgement and expertise of many humans, before and after training.
Software bits have been copyrighted for so long, there are 5¼" floppies with "(c) 1977" printed on them.