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You can download the RenderMan Installer, for the platform you're running.

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When you run the installer, it will ask you to input your forum username, password, and serial number. 

Next, make sure to select RenderMan Pro Server and RenderMan for Blender from the list and click Next. RenderMan Pro Server will then automatically install for you. For RenderMan for Blender, see the instructions below under the Installing section.

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GitHub

If you are a developer, you can also clone RenderMan for Blender from the RenderMan GitHub repository: https://github.com/prman-pixar/RenderManForBlender

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