I was curious about the i4i v. Microsoft patent infringement case, so I did a little more research into it. I’ve seen a lot of tech blogs and news sources that give a cursory examination and all seem to be parroting each other, so I thought I would give another point of view.
To clarify what some other reports have misstated, it’s not XML (eXtensible Markup Language) itself that’s at issue since it’s an open standard. It’s the use of Microsoft's "Custom XML" as a type of metacode for storing and manipulating documents and information about the documents and their data. Specifically, using a "metacode map" to distinguish the Custom XML from the content stream. This is a key distinction since many people have speculated cynical reasons for i4i targeting Microsoft and not every software vendor that uses XML or even going after the XML standard itself.
It could be that i4i has gone after a high-value target both in depth of pockets and visibility in order to scare smaller vendors into paying licensing fees preemptively. However, I think they went after Microsoft Word because it does appear to violate the patent filed 15 years ago and granted in 1998.
Microsoft has raised the two most common objections to patent infringement suits. First, the “I didn’t do it” defense also known as a lack of infringement. Second, the “nuh-uh” defense also known as patent invalidation. I’m not sure what the outcome of this is going to be, but it looks like Microsoft’s best defense is going to be pursuing the lack of infringement argument in appeal. The patent invalidation defense would prove more difficult since the patent was filed in 1994. In order to show that it’s invalid, Microsoft would have to show “prior art,” meaning that the technology was in use prior to the patent filing, therefore the patent should not have been granted.
Unfortunately for Microsoft, appellate courts assume, barring glaring evidence to the contrary, that the finders of fact (the lower court) were correct and therefore assume the facts to be exactly as presented in the lower court’s decision. Therefore it’s much easier to win an appeal on procedural grounds than on the merits.
I’m interested in seeing Microsoft’s reaction if the decision is affirmed on appeal. Since they’ve been barred from selling, advertising, or supporting Word in its current form, I think a basic cost/benefit analysis will show that a settlement with i4i for licensing fees will be the cheapest way out of this for Word 2003 and 2007. For Word 2010, Microsoft could always use their native XML document format for which they just received a patent. Retooling Word 2010 on short notice could be very costly unless, of course, Microsoft had been coding it with the expectation of losing this battle all along.