Source: https://www.trojanlawoffices.com/faqs/how-long-is-the-life-of-a-patent/
Timestamp: 2019-04-18 10:31:46+00:00

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The patent law provides that the life of a patent is no longer than 20 years from the date that the patent application was filed, and no shorter than 17 years from issuance. Depending upon how fast the patent office issues your patent can significantly impact the total length of the patent term. The patent office is obligated to review your patent application within 14 months of the filing date. For every day that the patent office delays in issuing an office action after 14 months, it must add a day onto the life of the patent.
There are other adjustments to the patent term that are made based upon Patent Office delays. For example, a day must be added to the patent term for each day that the issuance of the patent is delayed after three years from the patent application filing date.
While delays by the patent office can add time onto your patent, delays by you or your Los Angeles patent attorney in responding to office actions can subtract time from the life of your patent. While legally you have a right to wait as long as six months to respond to an office action, time will be subtracted from your patent term adjustment if you wait longer than three months. When you receive an office action from your patent attorney, take the three-month deadline seriously to avoid shortening the life of your patent. Make sure your patent attorney takes the three-month deadline seriously, too.
Another critical issue that can severely impact the length of your patent is the filing of a Request for Continuing Examination (R.C.E.). Filing an R.C.E. can completely wipe out all the time that the Patent Office would add to your patent for Patent Office delays. Then why file an R.C.E. at all if significant additional patent life is at stake? There are several factors to consider. To understand them requires a short explanation of the process for appealing rejections.
It is common for the Patent Office to initially issue a rejection of a patent application because the patent examiner believes your claimed invention is already known to those skilled in your field. This first rejection is called a Non-Final Rejection. You have a right to respond to a Non-Final Rejection by amending your patent claims to avoid the problem and/or explain to the patent examiner why he or she has misinterpreted your inventor or the prior art. The examiner responds by either agreeing with your amendments or argument or by rejecting the application a second time. This second rejection is usually a Final Rejection. The examiner can permit you to respond, but is not obligated to do so. Usually, you must appeal the final rejection.
But if the examiner has raised new arguments in the Final Rejection, you may feel your best chances on appeal would be improved if you had another chance to amend your patent claims. You cannot amend on appeal. You can buy another round of amendment and argument before the examiner by filing an R.C.E. so you can set the case up for a better chance on appeal. Sometimes the appeal becomes unnecessary because the examiner reaches agreement on the scope of the claims after the R.C.E. is filed, but this occurs at a high cost if Patent Office delays would have added significant time on to the life of your patent.
For patents in which the value is greatest in the years toward the end of the life of the patent, such as with pharmaceutical patents, even a one month loss in the length of the patent term can equate to a multimillion dollar loss. Therefore, if the nature of the invention is such that it will have the same or more value in 17 years, then an R.C.E. should only be filed as a last resort. Some inventions have a shorter half-life, which means the benefits of an R.C.E. may outweigh the detriments. Sometimes, filing an appeal can cause the examiner to pull back the Final Rejection and allow further prosecution because the examiner believes your appeal arguments have merit. This results in the benefits of an R.C.E. without the loss of a portion of the patent term. The bottom line is that an R.C.E. should not be filed reflexively without considering the impact on any patent term extension to which you may be entitled.
The Federal Circuit Court of Appeals has decided an important case involving the length of patent term adjustments (PTAs) that are granted due to delays by the United States Patent and Trademark Office (PTO) during patent prosecution. In Wyeth v. Kappos, No. 2009-1120 (Fed. Cir. Jan. 7, 2010), the Federal Circuit rejected the PTO’s interpretation of 35 U.S.C. § 154, the statute governing patent terms. Many newly issued patents will be positively impacted by the decision, as many patents will be enforceable for an additional period of protection added on to any previously calculated Patent Term Adjustment (PTA).
The general rule for patent terms can be found under 35 U.S.C. § 154(a)(2), which establishes the patent term at twenty years from the filing date of a successful patent application. Since the clock begins to run on the day of filing, and not when the patent is actually issued, the statute provides several term adjustment provisions in the event of PTO delay in issuing the patent. One of the adjustment provisions, § 154(b)(1)(A), provides a one-day extension of the patent term for every day that the issuance of a patent is delayed by a failure of the PTO to comply with its own deadlines (often referred to as “A” delay). Another adjustment provision, § 154(b)(1)(B), provides a one-day extension of the patent term for every day greater than three years after the filing date that it takes for the patent to issue (often referred to as “B” delay). A third provision—though not at issue in Wyeth—provided a one-day extension for every day the issuance of the patent is delayed during the prosecution of interferences, successful appeals, and secrecy orders (often referred to as “C” delay).
At issue in Wyeth was the interplay of these three provisions. Specifically, it was disputed when A delay and B delay “overlap.” The PTO’s interpretation of the statute has been that these two periods always overlap, and therefore a patentee is awarded either A delay or B delay—whichever is greater—but never a combination of the two periods.
On the other hand, Wyeth argued that the adjustments from both A and B delays can only overlap when they occur on the same day, and thus the two periods should be combined to the extent they do not occur on the same day or days. Thus, because B delay does not occur until after the first three years, any A delay that occurs within the first three years from the filing date (before B delay begins counting) will be added to any subsequent B delay. However, any A delay after the first three years from the filing date (after B delay begins counting) will be considered overlapping and not counted.
Prior to this ruling, the PTO would reject requests to correct patent terms based on the arguments presented in Wyeth, even in light of the district court’s acceptance of that argument and rejection of the PTO’s interpretation. However, with the Federal Circuit’s decision, the PTO finally announced that it will change the manner in which it calculates PTAs, and is preparing guidance for expediting requests for recalculation of patent term adjustments in light of the Wyeth decision. Further, the PTO announced that it would not seek further review of the Wyeth v. Kappos decision. Thus, many patents that had been pending for more than three years before issuance will now be entitled to additional time under the PTA. For some patents, the increase in time will be significant.
However, the time to act is limited. For applications that have received a Notice of Allowance, under Rule 1.705, a petition to correct PTA must be filed before the issue fee is paid. For recently issued patents, a petition to correct PTA must be filed within two months of issue. Finally, patentees dissatisfied with the PTO’s determination must seek review by filing a civil action within 180 days of patent issuance.

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