Ouch. A couple of employees from the Microsoft Visual Basic Team apparently filed a patent on the IsNot operator - yes, something like a "not equal to", but for object references instead of values - what a bunch of nonsense. And cheekily, they also claim in their application that Borland Delphi is a Basic derivative — while ignoring the fact that Delphi is Pascal, which has a quite different history...
The whole thing has the feel of a joke, but unfortunately it appears to be true.