The fact this patent was granted in the first place seems completely absurd. But then again, we live in a world where Boeing has a patent on certain trajectories that use the moon's gravity (http://www.google.co.uk/patents/US6116545), so it shouldn't really surprise me.
I recall a story a while back about a satellite that ended up in the wrong orbit after launch. The engineers knew how to correct it using various orbital maneuvers, but alas those maneuvers were patented and it was too expensive to license them. So the decision was made to splash the satellite and let the insurance companies pay out. At least that's my recollection...
Edit : Here's a description of the issue, which is a bit different than my recollection
> But then again, we live in a world where Boeing has a patent on certain trajectories that use the moon's gravity
Interesting. That particular patent was owned by Hughes Electronics, though, not Boeing [1]. EDIT: Apparently in 2000 Boeing acquired that division of Hughes Electronics [2] but the transfer of ownership of the patent was never recorded in the USPTO.
The patent expired in 2012 because the owner didn't pay the required "maintenance fee," which is a statutory fee that must be paid every few years to keep a patent alive [3]; see the end of the document to which you linked.
The patent system as it exists encourages this kind of behaviour. It's hardly surprising that people would take advantage of it. If he didn't do it, someone else would and a patent case to prove prior art gets expensive.
