The large backlog of cases at the PTO has added greatly to the problem of long patent application pendency. There are other contributors to the problem – such as applicants and examiners unwilling to reach a compromise solution (often based on the demands of superiors).
To provide some measure of pendency, I created a database of 20,000+ randomly selected patent applications and issued patents filed 2000 - 2007. For each of case, I tallied the final status as of mid-July 2009. (Status is either patented, abandoned, or pending). Using that data, I created a chart of the percent of utility applications still pending as of July 2009. This data can be helpful for someone considering whether their still-pending application is an anomaly. Over 84% of the applications filed in 2007 are still pending (+/– 2% at 95% CI) , while less than 1% of applications filed in 2000 are still pending (+/– 1% at 95% CI).

The second chart standardizes the same data according to the amount of time in prosecution.

Notes:
- This data only includes applications that were either (1) published or (2) patented. I do not know the percentage of cases unpublished cases that are still-pending versus those that are abandoned.
- The data presented here does not distinguish between technology centers, continuations, etc. The still-pending rates varies considerably within those different categories.
- The pendency rate for applications filed Q4 2004 appears unexpectedly high and the rate for Q1 2005 appears unexpectedly low.. That is at least partially explained by a data collection artifact. My data sample includes a relatively large number of applications filed in late December 2004 and early January 2005 rather than being more evenly distributed throughout the respective three months.



