If only there were some way of finding out for certain, we wouldn't have to idly speculate...

Patents last too long for "waiting for expiry" to be a useful strategy for hardware or software, most of the time; copyrights last even longer. And even a copyright expiry doesn't help you if you don't actually have the source-code in question; related reasoning was behind the original stipulation in the UK that copyright was only granted on printed matter if copies were deposited at the British Library, Oxford, and Cambridge -- but the Berne Convention essentially outlawed such restrictions.

Peter