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7-Zip Rule

Modified or wrapped 7-Zip source code must stay under the LGPL or GPL; other application code may use any licence

Catalog row in Vendor License Rules · Cited

Kind
Restriction
Statement
7-Zip FAQ, Developer FAQ (undated; as published on 2026-09-27): LGPL code must remain licensed under the LGPL. Changed 7-Zip code, or a wrapper compiled into a DLL, must have its source (including modifications, additions and wrapper) licensed under the LGPL or GPL; any other code in the application can be licensed as the developer wishes. LGPL 2.1 §2(c) requires the whole of a modified work to be licensed at no charge to all third parties under the licence.
Applies when
Changing 7-Zip source code or compiling part of it, with a wrapper, into a DLL.
Applies to
7-Zip source code incorporated into another application.
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