Just found relevant thread on reddit:
https://www.reddit.com/r/Bitcoin/comments/3mhe5p/case_wallet_teardown/.
"As we are using secure elements, we are bound by NDA to not reveal the chip's APIs (this is part of the current security by obscurity model of this kind of architecture). Therefore we cannot publish our source code, nor could you compile yourself anyway, by lack of tools.
The attestation being embedded in our firmware, it is therefore not open source either."
That's about Ledger Nano/HW.1 (that you can verify with your own set of tests against
), not Case.
Also getting source code for an hardware product doesn't mean much if you're not able to validate which source code said hardware product is running in the field.