<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> Is this real? Seems that patents don't have any limits... <br /> Posted by Zipi</DIV></p><p>Unfortunately, that sounds entirely plausible. You can patent anything you want, provided the patent clerk isn't reading it too carefully -- and they get so many patent applications that a lot of stupid patents slip by them. They mainly make sure there isn't a similar patent already, without checking to see if it's legitimate in other ways. For instance, you can patent things which don't exist, and that can be totally legitimate -- you're patenting the idea, theoretically in hopes of eventually making it practical and making money off of it. A legitimate patent is supposed to be something which is novel. So if there is "prior art" (somebody's done it before), the patent can be invalidated. Certainly gravity assists have been done before, including ones involving the Moon. There was even a scientific spacecraft (Japanese, IIRC) which was stranded in the wrong orbit but saved by gravity assists, so prior art certainly exists. The technique also cannot be obvious, though this is a bit of a judgment call. One could argue that to anybody who knows anything about celestial mechanics, this fails the obviousness test.</p><p>Bottom line, this patent would not stand up to a legal challenge. The problem with patents is that you'd have to *pay* to mount a legal challenge. Sure, you might be able to sue to recover court costs, but you'd have to have enough capital to keep the court case going long enough. Large corporations thus have an unfair advantage in this kind of patent battle, and some particularly unscrupulous companies have deliberately exploited patent law for profit. (Copyright law has also been exploited in this way. SCO attempted to do this when it obtained copyright to certain Unix source code, but made the fatal mistake of going after IBM first. This tactic really only works when attacking smaller entities, since the real intent is not to prevail in court but to intimidate potential defendants into settling out of court and/or paying license fees.) There have been some notable cases in the software arena in recent years, with Amazon's One-Click Technology being one of the more infamous. Amazon was not attempting to profit from patent protection lawsuits but was instead attempting to defend its market share by preventing others from competing. They had patented the idea of being able to buy an item from a website with a single click. This patent was ultimately overturned, as the idea is ridiculously obvious, and Amazon wasn't even the first to use it. But like all invalid patents, it stood until it was successfully challenged in court.</p><p>Boeing's patent will probably also stand until it is successfully challenged in court. </p> <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em> -- The Tenth Doctor, "Blink"</font></p> </div>