As of now, ActivityStream lacks any sort of copyright and licensing information, both on PyPI or in the codebase itself.
It's probably a minor issue since the code, I believe, has been developed in-house. But from Allura perspective it's still and external dependency and hence it's copyright status should be as clear as possible.
Activity stream was developed by SourceForge/geeknet. We should license it under the Apache License 2.0