The official 2026.09.05 release includes GPL-2.0 license text, the PSoXide notice, hashes and an exact corresponding-source commit. Known CC0 components include documented OpenGameArt/Kenney gameplay effects, Brian MacIntosh UI placeholders and Kenney controller prompts.
Provenance caveat: upstream notes distinguish several author-supplied recordings from those CC0 assets and do not record separate upstream terms for each recording. The official assembled release is distributed under its included GPL notice; the audit does not mislabel those recordings as CC0.