IsNot is not a trivial software patent

We find it hard to believe that the highly skilled software developers at Microsoft (or their well-known colleagues at Microsoft Research) are unaware of the prior art mentioned above. It is also striking that prior art occurs in one of Microsoft's own products (the language C#). One is tempted to speculate about the intentions of the applicants and their sponsors with this particular patent application. Several possibilities come to mind:

• They think that the subject matter is new and this should be the default assumption. This raises the question whether there exists (or should exist) a form of ``patent etiquette'' that assumes that applicants truly consider their invention as new. According to Park [27], there is no explicit duty of disclosing prior art in the European Patent Office, whereas the Patent Offices in the US and Japan require the applicant to disclose the closest prior art that he acknowledges when the patent application is filed. In the US this is done in a separately filed ``Information Disclosure Statement'' (IDS). See Section 8.9 for a further discussion of this topic.

• They find that the matter of trivial patents and determining prior art need clarification and that filing a patent application is the fastest road to achieve this goal, independent of the likelihood of acceptance. This defines the future options for patenting relatively simple inventions. When rejected, the application builds up prior art and may be used to provide indemnity to clients against intellectual property claims.

What if our first analysis from a computer science perspective is too naive? Is it still possible to discover some form of innovation or hidden meaning in this application that merits its acceptance? We see the following possibilities for this:

• The patent application is about the specific naming of the comparison operator. This is suggested by the explicit phrase in the patent application we cited above: ``Any suitable case sensitive or case insensitive tag for the operator is contemplated by the invention, such as, but not limited to ...''. This would mean that the application is not about the idea of an inequality operator but about the specific form of that operator. In this way, the application would establish a form of copyright on the operator name ``IsNot''.

• The specific context of BASIC is the substance of the application. This also makes finding prior art hard.

• By patenting this specific operator in BASIC, alternative implementations of the language can be discouraged, or at least interoperability is hindered.

• Although claim 1 of the patent application is broader than any of the preceeding three possibilities, the patent applicant may have written claim 1 for the strategic reason of giving the patent examiner an easy claim to reject, thereby leaving the remaining (narrower) claims and providing the examiner with a feeling of having done his job.

• The patent application is not concerned with the IsNot operator or the inequality operator at all. They just serve as a smoke screen to hide an idea in one of the 23 other claims. Is the patent about giving an error message when an operand of the IsNot operator is missing? Is this patent about BASIC-compilers using a certain compiler organization? As far as we can judge these claims describe common practices in compiler construction and language implementation and cannot be considered to be inventions. This does, however, not mean that it is easy to find prior art since most of the claims are very specific and may not occur in the literature. We invite the reader to investigate these claims and to challenge our analysis.

• The application has yet an other meaning, for instance, challenging the patenting system. In this case, we really congratulate the applicants for their brilliant contribution. Some implications are further discussed in the remainder of the paper.