FangZheng fonts are proprietary intellectual property. Distributing or using a "patched" version without a valid commercial license is typically a violation of copyright law. The patch itself modifies the software protection mechanisms, which may be illegal in certain jurisdictions (anti-circumvention laws).
Patching enables:
Original FangZheng fonts are known for strict Digital Rights Management (DRM) and licensing protocols. A "patched" version usually addresses one of the following technical issues: