Caveat emptor. The license only gives you permission to use the code, not any patents covering it. So while you can read the code, to use it you need to either

Caveat emptor. The license only gives you permission to use the code, not any patents covering it. So while you can read the code, to use it you need to either get a separate patent license or convince yourself that MS holds no patents on the code. I'm not going to do a patent search, nor do I want to know, but I would be surprised if they haven't patented aggressively.