By Jason Rantanen
Last fall, I presented a set of data on inequitable conduct pleadings at the America Invents Act: One Year Later conference at the Indiana University Mauer School of Law. That data revealed two significant findings: first, that the rate at which inequitable conduct pleadings rose between 2000-2008 was much slower than previously believed (and never came close to the alleged 80% of all patent cases) and second, that since 2008 the rate at which inequitable conduct is pled has fallen substantially. The results of that study have since been published in IP Theory; you can read the relatively short article here: http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2266041.
Since the article only included data up to the end of 2012, however, I thought it would be useful to update it to include 2013 data. The below chart compares the number of patent cases in which an Answer was filed to the number of patent cases in which an Answer was filed containing the term "inequitable conduct" for each year based on searches performed in LexMachina. The 2013 data is as of 9/18/2013.
This chart indicates that the rate at which inequitable conduct is being pled continues to decline (at least measured through this crude metric), although it may have reached a plateau. I've also generated a similar chart that shows Answers containing "inequitable conduct" as a percentage of all "Answers" in patent cases that are searchable using LexMachina; it shows a similar pattern.