In usa everything that is copyrightable, becomes copyrighted at moment it is created. For instance that sentence, and this on, are protected works owned by me. The only reAson HN can legally use then is cause I gave them license, buried somewhere in Eula/site terms of use.
Also, an architecture is not copyrightable. Maybe patentable. Copyrights protect specific expressions, not a general idea, plan, or architecture. At least not yet thankfully I haven't seen anyone try to argue an unrelated software doing same thing is a derivative work.
But Twitter has a patent pledge with its engineers [1]:
The IPA is a new way to do patent assignment that
keeps control in the hands of engineers and designers.
It is a commitment from Twitter to our employees that
patents can only be used for defensive purposes. We will
not use the patents from employees’ inventions in
offensive litigation without their permission. What’s
more, this control flows with the patents, so if we sold
them to others, they could only use them as the inventor
intended.
Many big companies will patent their internal architectures. I've been involved in the creation of quite a few patent applications of exactly that. My name is even on one of them.
It's silly and ridiculous but necessary because of the way patents are enforced.
I can promise you that the existence of the patent system did not motivate us to build any of that software, but it certainly motivated us to patent it after the fact, so that someone else couldn't patent it and then sue us for having independently built the same thing.
Also, an architecture is not copyrightable. Maybe patentable. Copyrights protect specific expressions, not a general idea, plan, or architecture. At least not yet thankfully I haven't seen anyone try to argue an unrelated software doing same thing is a derivative work.