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Yeah, if one person on the team licenses the code and then shares it with the rest of the team (who have not paid their $19 dues), then it would be a breach of your agreement with Epic.b. Distribution to other licensees - You may Distribute Engine Code licensed to you under this Agreement (including as modified by you under the License) in Source Code or object code format, or any Asset provided to you without additional charge by Epic, to an Engine Licensee who has rights under its license to the same Version of the Engine Code or Asset that you are Distributing.
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Can I share the Unreal Engine source code or tools with others?
You can share the source code or tools, along with any modifications you’ve made, with anyone who is an Unreal Engine licensee who is authorized to access the same version of the engine as yours, e.g. the 4.x.x version number of your installed build.
Whenever you update, everyone on the team has to pay the $19 again to update to the new version.