Patent laws are different in many countries, and inventors are sometimes at a loss to understand which basic requirements should be satisfied if an invention is to be granted a patent. This is particularly true for inventions implemented on a computer. While roughly a third of all applications (and granted patents) relate, in one way or another, to a computer, applications where the innovation mainly resides in software or in a business method are treated differently by the major patent offices in the US (USPTO), Japan (JPO), and Europe (EPO).

The authors start with a thorough...