Glyn Moody has an interesting piece on Why Patents are Like Black Holes where he looks at the situation when a large patent holder goes bankrupt - or is about to. His point is that even if a company otherwise can go out of business cleanly, the patents often remain as a piece of "IPR" that can come back and haunt us like a zombie.

Also Matt Asay recently weighed in on the subject:

This blog post was originally posted on November 10, 2008. It was then withdrawn the next day and replaced with the short explanation below. Since the person who asked me to withdraw it has since left Sun, I have left Sun, and Sun itself will not exist anymore in a few days, I have decided to re-publish the original text for historical purposes.