Recently, one of my colleagues received a notice from the USPTO stating that a granted patent was subject to a PTA of 2038 days.
What is a PTA? A patent term adjustment (PTA) accounts for delays in the patent office's action examination and delays by the applicant in responding to an office action (eg, not responding with three months which counts against you).
There is another adjustment available to patent owners. A patent term extension (PTE) accounts from regulatory delays that affect when a product can be marketed (eg, FDA review) and you can get up to 5 years (separately from a PTA).
The goals of the PTA and PTE are to allow patent holders to enjoy the full 20 year patent term from the first non-provisional patent application filing.