By Dennis Crouch
Once a patent issues, the patentee must pay a regular maintenance fee to keep the patent in force. The PTO offers a six-month grace period following the due date where the maintenance fee can still be paid (plus a surcharge) without justifying the delay. At that point, the patent is deemed expired. However, the USPTO allows subsequent revival under either the (low) unintentional or (high) unavoidable standard.
The chart above shows data for patents that were revived (data through April 8, 2014). The chart shows a steep decline in revival that began in 2011. If Q1 of 2014 is indicative, this year there will be fewer than 200 of these revivals. At this point, I don’t know the cause of the steep decline – thoughts on why?