BTW im talking about shader "code" such as can be seen in .fx files.
Yes. Shader code, like all other code can be protected by copyrights, and where permitted by law, software patents.The language used is not important as to what kind of code can be patented.
Just like nobody can copyright
Sure they can. They can even patent it. Whether it stands up in court depends entirely on whether the defendant can prove beyond a shadow of a doubt that prior art had existed.