Using std::move with std::shared_ptr

I have a function defined as follows:

void foo(std::shared_ptr<X> x) { ... };

If I declare a shared ptr to X:

std::shared_ptr<X> sourcePtr(new X(...));

I can then call foo as follows:

foo(std::move(sourcePtr));

or

foo(sourcePtr);

I understand that if I use the first option then sourcePtr becomes null. Does it also prevent the reference count from being incremented?

If that doesn't matter, which option should I prefer? Should I be considering anything else when making such a decision?