Litigation and post-grant proceedings often go hand-in-hand. A new litigation report published by Lex Machina summarizes patent litigation data for 2013 and prior years.  It is an interesting report and very easy to digest.  Two findings caught my eye.  The first one relates to the overall number of patent litigation cases filed in 2013:

Plaintiffs filed 6,092 new patent cases in U.S. District Courts in 2013 . . .

The second finding is the number of U.S. Patents at issue in those filings:

4,917 patents were at issue in all cases filed during 2013.

That second number is surprising, because if understood correctly, the findings indicate that about 5 out of every 6 lawsuits filed in 2013 relate to different patents.  That ratio seems high — especially in view of the AIA litigation joinder provisions.  However, if we assume these numbers are roughly correct, they show a large difference between the number of patents asserted and the petitions filed in the PTAB.

For example, compare Lex Machina’s reported 4,917 patents at issue in 2013 suits with the 1,312 total IPR and CBM petitions on file in the PTAB from September 16, 2012 to May 8, 2014.  These numbers indicate that  at most about 1 out of 3 patents in litigation are the subject of a PTAB petition.  If true, that means several patents in litigation have not been submitted for review by the PTAB.

Of course, bear in mind that this is just a rough, unscientific approximation because:

• not every petition in the PTAB relates to a new patent,
• not every patent being challenged in the PTAB is in litigation, and
• this crude approach does not attempt to correlate the petitions before the PTAB with a certain year of patent assertion.

Not every patent in suit is eligible for a post-issuance proceeding in the PTAB, so there is no reason to expect that every patent in suit will be the subject of a petition.  But, this data seems to indicate that there is still a large number of litigated patents that could be subject to future post-grant challenges. Readers are invited to contact me with better data than this admittedly rough approximation.  Please send me that information and I will try to post it to give a more accurate representation of patents in litigation versus those challenged in the PTAB.