Microsoft Patents 'IsNot'

Peter Maas peter at
Sat Nov 20 22:20:28 CET 2004

Jeff Shannon schrieb:
> Peter Maas wrote:
>> Isnot is semantically equivalent to the inequality operator which is
>> some hundred years old.
> Actually, looking at the patent claim, this is *not* semantically 
> equivalent to inequality.  It specifically mentions 'isNot' as something 
> that compares memory addresses, which in Basic are normally hidden.

Isnot is the inequality operator applied to memory addresses. That these
are hidden in VB, doesn't make this a new invention worth to be protected.
E.g. electrical power supplies are a pretty old thing. If somebody would
try to get a patent on the application of electrical power supplies to
TVs this would probably (hope so) rejected and so should the application
of the inequality operator to memory addresses.

> It's still a pretty questionable patent, though.  Even without anyone 
> explicitly having used 'is not' in Basic before, its prevalence in so 
> many other languages would seem to fail the "nonobvious" test 
> (supposedly) required for patent validity.

Could this patent be circumvented by writing "not (a is b)" instead
of "a is not b"? If that would be the case the patent claim would
be even more ridiculous.

Peter Maas,  M+R Infosysteme,  D-52070 Aachen,  Tel +49-241-93878-0
E-mail 'cGV0ZXIubWFhc0BtcGx1c3IuZGU=\n'.decode('base64')

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