# Can I use GPL code in proprietary software?

**Short answer:** Modify and distribute commercially: Yes.

GPL-3.0 allows commercial use, modification and distribution, on condition that distributed derivative works are licensed under the GPL with source available.

## Modify and distribute commercially — Yes

License: [GNU General Public License v3.0](https://www.gnu.org/licenses/gpl-3.0.html) (`GPL-3.0-only`, curated)

- Every use you described is granted by GPL 3.0, and nothing you described is prohibited.

Duties: attribution, license_notice, state_changes, share_alike, source_disclosure

## Context
- Distributing a closed-source product that includes GPL code conflicts with the GPL's source-disclosure duty. Internal use without distribution does not trigger it.

## Sources
- [GPL-3.0](https://www.gnu.org/licenses/gpl-3.0.html)

## Check it yourself (free, no key)
```json
{
  "tool": "check_license",
  "arguments": {
    "license": "GPL-3.0-only",
    "intended_use": {
      "commercial_use": true,
      "modification": true,
      "redistribution": true
    }
  }
}
```
REST: POST https://www.rightshold.com/v1/licenses/check

_Computed from Rightshold's license profiles; not legal advice. Updated 2026-10-19. JSON: https://www.rightshold.com/answers/can-i-use-gpl-code-in-proprietary-software.json_