As the rumor mill never stops churning, this is a mix of fact and rumor. Fact is, the patent is very real, but the rumor (or speculation around the fact) is feasible, but still a rumor.
Sony has officially patented technology that would allow the next console (PS5?) to feature backwards compatibility. Even more interesting, the patent isn’t simply restricted to the PS4, but it includes backward compatibility for the PS3, PS2 and the original PS1. This quite a hefty patent indeed.