[글로벌] 미국 특허 소송에 쓰이는 특허의 건수, 나이는 얼마나 될까?

미국의 연간 특허소송 건수는?
           대략 3,000건 정도 (참조 : http://dotomari.com/227)
한 해에 특허 소송에 사용되는 특허의 건수는? 
           아래 블로그의 저자가 확인한 바에 따르면 2009년에 3,404개 특허
           이 건수는 지난 10년간 평균 특허등록 건수의 약 2%.
특허 소송에 사용되는 특허의 나이는? 
           55%가 5년 이상, 24%가 10년 이상.
재심사(Reexam) 청구율은?
           578건(17%)
 

출처: 
Patents, Litigation and Reexaminations

By Jason Rantanen

The number of patents involved in litigation
The number of patent suits filed each year is well known.  But what about the number of patents involved in those cases?  Mark Lemley and others have estimated that about 1-2% of all issued patents have ever been litigated.  To test this estimate, I searched the LEXIS utility patents database using the LIT-REEX field to identify all patents that were flagged as the subject of litigation filed in the year 2009.*  I ended up with 3404 patents, or approximately 2% of the average number of utility patents that the PTO issued annually over the previous decade. 

This result provides further confirmation of the conventional belief that the vast majority of patents are never litigated - especially since I suspect it overstates the percentage of patents involved in litigation, as it assumes that the litigation flag is limited to just infringement suits (as opposed to inventorship disputes, for example) and it does not take into consideration the fact that some patents are the subject of multiple suits filed in different years.  

How old are these patents? 
The below chart shows the age of the patents involved in suits filed in 2009.  More than half (55%) of these patents were at least five years old as of the litigation filing date; 24% were over ten years old. 

What about reexamination requests?
The above chart also shows the number of patents involved in suits filed in 2009 that have ever been the subject of a reexamination request.  Of the 3404 total patents, LEXIS reports that reexams were requested at some point for 578 (17%).  Many of these requests were filed in 2009 or later (likely as part of a litigation strategy): 398, or 11% of the total number of patents involved in suits filed in 2009 were the subject of a reexam request in 2009, 2010, or 2011.

*I used 2009 because the 2010 and 2011 results were affected by the numerous false marking suits filed in those years.