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License answers

Can I use zlib commercially, in AI training or with modifications?

Use for any purpose, including commercial, and alter and redistribute freely, as long as you do not misrepresent the origin, mark altered versions, and keep the notice in source distributions.

UseAnswerWhy
commercial_useYesPermitted, with duties: license_notice, state_changes, no_misrepresentation.
model_trainingNeeds human reviewThe license grants broad rights but attaches conditions (such as keeping notices) to copies and adaptations. Whether a trained model, or its output, is a copy or adaptation that carries those conditions is legally unsettled, and in some places training may fall under an exception such as fair use. A human reviewer should confirm this use for your case.
modificationYesPermitted, with duties: license_notice, state_changes, no_misrepresentation.
redistributionYesPermitted, with duties: license_notice, state_changes, no_misrepresentation.
model_inferenceYesPermitted, with duties: license_notice, state_changes, no_misrepresentation.

Duties

license_notice, state_changes, no_misrepresentation

Check it by API (free, no key)

curl -s https://www.rightshold.com/v1/licenses/check -H 'content-type: application/json' \
  -d '{"license_id":"Zlib","intended_use":{"uses":["commercial_use","model_training"]}}'

MCP: call check_license at https://www.rightshold.com/mcp. Connect your agent · Full reading · Legal text

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