unRAR-derived code may not be used to re-create the proprietary RAR compression algorithm; modified unRAR sources must say so
Catalog row in Vendor License Rules · Cited
- Kind
- Restriction
- Statement
- 7-Zip License for use and distribution (undated; as published on 2026-09-27): the RAR decompression engine was developed using unRAR source code, whose copyrights belong to Alexander Roshal. The unRAR sources cannot be used to re-create the RAR compression algorithm, which is proprietary. Modified unRAR sources may be distributed separately or in other software only if the documentation and source comments clearly state that the code may not be used to develop a RAR (WinRAR) compatible archiver.
- Applies when
- Modifying or reusing 7-Zip RAR decompression source code.
- Applies to
- RAR decompression code in 7z.dll and the CPP/7zip/Compress/Rar* source files.
- Related programs