That is not entirely true. As stated elsewhere, there is likely an implicit patent license provided by the BSD. The reasoning is basically, "we are [copyright] licensing this cod e to you to use, so [therefore] we must also be providing a corresponding patent license to use the code."

Legal scholars are mixed on that, and it hasn't been tested in court.

But that implicit license is certainly better than the explicit license in FB's code.

To sum up: you may be worse off with BSD+Patents.