A patent novelty opinion is a determination of whether the invention in question has prior art that discloses the invention. In other words is the patent actually new.
A novelty opinion is sometimes also called a patentability opinion. But the novelty opinion is actually only a part of the patentability opinion.
Novelty is required for the claims in a patent application to be patentable. The lack of novelty is likely to result in a patent examiner rejecting the claims that are not new according to the prior art.
If the idea is patent eligible subject matter, useful, novel, non-obvious, and a complete and proper patent application is filed and allowed; then, yes, you can patent an idea for an invention without having the actual invention.
Read More Can You Patent an Idea?Patentability is a combination of two expert evaluations to address all four patentability requirements: 1. patent eligible subject matter, 2. useful, 3. novel, and 4. non-obvious.
Read More What does Patentability mean?