There is no sense, in C++, in which a naked pointer implies or suggests ownership. It is the opposite: the continued validity of a pointer value depends on ownership maintained elsewhere. Nowadays libraries keep track of ownership. Most commonly the library delegates that responsibility to Standard std::unique_ptr, for familiarity. Not doing that indicates something different in play.

(It is, in fact, UB even in C to copy the value of a pointer to an object that does not exist anymore. This is the case regardless whether it had pointed to or into a stack or a heap object.)

In C, there is no way to express library ownership of a pointer. So, in C there is always potential for confusion about ownership.