Looks like it's distributed under Apache 2.0, which means it's open source. Whether they take contributions or not is not really relevant to open-sourceness --

Looks like it's distributed under Apache 2.0, which means it's open source. Whether they take contributions or not is not really relevant to open-sourceness -- under an appropriate license anyone can use the source to run their own project with whatever contribution policy they like -- but it looks like the main distributor is indeed open to contributions: https://www.osehra.org/content/code-contribution https://www.osehra.org/content/code-contribution