source-sdk-2013/CONTRIBUTING

Thanks for your interest in the Source SDK 2013 project.  When you make a
contribution to the project (e.g. create an Issue or submit a Pull Request)
(a "Contribution"), Valve wants to be able to use your Contribution to improve
the SDK and other Valve products. 

As a condition of providing a Contribution, you agree that: 
- You grant Valve a non-exclusive, irrevocable, royalty-free, worldwide license
to make, use, sell, reproduce, modify, distribute (directly and indirectly),
and publicly display and perform the Contribution, and any derivative works
that Valve may make from the Contribution, under any intellectual property you
own or have the right to license. 
- You warrant and represent that the Contribution is your original creation,
that you have the authority to grant this license to Valve, and that this
license does not require the permission of any third party.  Otherwise, you
provide your Contribution "as is" without warranties.  

Should you wish to submit a suggestion or work that is not your original
creation, you may submit it to Valve separate from any Contribution,
explicitly identifying it as sourced from a third party, stating the details
of its origin, and informing Valve of any license or other restriction of
which you are personally aware.