Legal Boundaries (code vs original game assets)
The legal line that keeps a re-implementation safe is new code you may write and license freely versus original assets you may neither copy nor redistribute — the user must own and supply those.
Why it matters
Get this wrong and the project is dead: bundling copyrighted sprites or music invites a takedown, and copying decompiled code makes the whole codebase a derivative work. Every contributor to OpenClaw must internalize where the line sits, because one tainted commit endangers everyone’s work. (Note: this is engineering guidance, not legal advice — laws vary by jurisdiction.)
How it works
Sort every artifact into one of three buckets:
| Artifact | Copyrightable? | May the project ship it? |
|---|---|---|
| New engine source code | Yes — owned by you | Yes, under your chosen licence |
| File-format byte layout | No (interface/fact) | Yes — document and publish freely |
| Sprites, levels, music, story | Yes — Monolith/owner | No — user supplies at runtime |
| Trademarks (“Captain Claw”) | Separate (trademark) | Avoid implying endorsement |
Two ideas do the heavy lifting. Idea/expression — the idea of “a tile-based platformer” is free; Monolith’s specific expression (its art, its levels) is protected. Interoperability — reverse-engineering a format purely to read your own data files is broadly treated as legitimate, which is why a WWD parser is fine but the level bytes are not yours to ship. See clean-room-vs-asset-dependent-ports.
Example
OpenClaw’s stance, made concrete:
- The repository ships engine code only; there is no
CLAW.REZand no extracted PNG/WAV in releases. - The README instructs users to provide their own retail data file.
- Parsers and format notes are public — describing structure, not redistributing content.
A contrasting unsafe move: attaching an “asset pack” to a GitHub release “for convenience”. That redistributes the copyrighted work regardless of intent.
Pitfalls
- CI fixtures with real assets — a test that needs a real
.PIDmust fetch it from the user’s install, never from the repo. - “It’s abandonware, so it’s free” — abandonware has no legal standing; the copyright still holds.
- Leaking assets through git history —
git rmdoes not erase prior commits; a rip committed once lives on until history is rewritten. - Decompiled snippets in issues/PRs — pasting original disassembly to “explain” logic can taint the discussion and any code derived from it.