The copyright in the source code primarily protects Mbed TLS (formerly known as PolarSSL). We own all the copyright in the source code. For code that is contributed to us, we request the original author to share the copyright with us.
We offer all the code under the GPL license so that projects can see and use Mbed TLS and PolarSSL as Open Source.
The PolarSSL brand name is trademarked in the US. You can see the trademark at USPTO for yourself.
You can also find more information about using the Mbed trademark.
Won't people use Mbed TLS or PolarSSL illegally?
Yes, they might. We'd rather have a flexible software product for our users, and run the risk that companies use Mbed TLS and PolarSSL without contributing back to the community.
If we ever find out, we will of course prosecute them to the fullest extent of the law.