A 37 CFR 1.136(a) extension of time lets a patent applicant push back the deadline to respond to most USPTO Office Actions by up to five additional months, in one-month increments, simply by paying a fee. No explanation is required, no examiner reviews your reasons, and you can file the extension at the same moment you file the response. The catch sits in two places: a hard six-month statutory ceiling you cannot cross, and a patent term adjustment penalty that kicks in for anything past the third month.
How the Automatic Extension Works
When an examiner mails an Office Action, it sets a shortened statutory response period, usually two or three months. Under 37 CFR 1.136(a), you can buy additional time in one-month blocks up to five months beyond that original deadline, or up to the statutory maximum, whichever comes first.1eCFR. 37 CFR 1.136 – Extensions of Time The rule applies to applications filed under 35 U.S.C. 111(a) and to PCT applications entering the U.S. national stage under 35 U.S.C. 371.2United States Patent and Trademark Office. Manual of Patent Examining Procedure Section 1896
The word “automatic” is literal. Nobody at the USPTO evaluates whether you deserve the extra time. File the petition, pay the fee, and the deadline moves.
Filing the Extension With the Response
Most practitioners submit the extension and the response together. The regulation treats payment of the extension fee alongside a response as a constructive petition, so a separate petition form is not strictly required. You can also include a blanket authorization in the application telling the USPTO to treat any late reply as incorporating an extension petition for whatever length is needed; an authorization to charge all required fees or all extension-of-time fees will do it.1eCFR. 37 CFR 1.136 – Extensions of Time
If you prefer to file the petition explicitly, the standard form is PTO/SB/22, submitted electronically through Patent Center with the fee.3United States Patent and Trademark Office. Petition for Extension of Time Under 37 CFR 1.136(a)
Extension Fees by Entity Status
Two variables set the price: the number of months and your entity status. The USPTO’s small entity discount is 60% off the large-entity rate; micro entity status brings 80% off, if you meet the additional income and filing-history requirements.4United States Patent and Trademark Office. Micro Entity Status
Current fees under 37 CFR 1.17(a):
- One month: $235 large entity, $94 small, $47 micro
- Two months: $690 large, $276 small, $138 micro
- Three months: $1,590 large, $636 small, $318 micro
- Four months: $2,495 large, $998 small, $499 micro
- Five months: $3,395 large, $1,358 small, $679 micro
You pay a single fee for the total number of months, not a stacked sum. Three months of extension costs the three-month fee. Claiming the wrong entity status can leave you underpaid, and an underpaid extension can leave the application abandoned.
How Many Months You Can Actually Buy
Federal law caps the total response time for any Office Action at six months from the mailing date, regardless of what you are willing to pay.6United States Patent and Trademark Office. Manual of Patent Examining Procedure – Section 710.01 Statutory Period The regulation’s five-month allowance is bounded by that ceiling.1eCFR. 37 CFR 1.136 – Extensions of Time
So the math depends on your original deadline. A three-month Office Action allows up to three months of extensions (three plus three equals six). A two-month Office Action allows up to four. Filing even one day past the six-month mark from the mailing date abandons the application, and no additional fee will save it.
Where 37 CFR 1.136(a) Does Not Apply
Several situations sit outside the automatic-extension mechanism. The regulation lists specific exclusions:
- Any Office Action that expressly states extensions under 1.136(a) are not available.
- Reply briefs before the Patent Trial and Appeal Board under 37 CFR 41.41.
- Requests for oral hearing under 37 CFR 41.47(a).
- Responses to PTAB decisions.
- Contested cases and derivation proceedings.
Once the USPTO mails a Notice of Allowability, certain deadlines set in that notice also become non-extendable, including the period for submitting the inventor’s oath or declaration, the period for formal drawings, and the period for biological deposits.1eCFR. 37 CFR 1.136 – Extensions of Time
Two traps deserve individual mention. After filing a notice of appeal, the two-month deadline to file the appeal brief under 37 CFR 41.37(a) is not extendable under 1.136(a). Miss it and the appeal is dismissed.7United States Patent and Trademark Office. Appeal Brief And ex parte reexamination proceedings are entirely off-limits for 1.136(a); extensions there run through a separate rule, 37 CFR 1.550(c).8United States Patent and Trademark Office. Extension of Time
When 1.136(a) is unavailable, a different mechanism, 37 CFR 1.136(b), allows an extension for cause. That petition must be filed on or before the day the reply is due, must demonstrate sufficient cause, and cannot push the deadline past the same six-month statutory ceiling.1eCFR. 37 CFR 1.136 – Extensions of Time
The Patent Term Adjustment Cost
Every month of extension past the third can permanently shorten your patent. Under 35 U.S.C. 154(b)(2)(C), any time an applicant takes beyond three months to respond to an Office Action counts as applicant delay and reduces patent term adjustment day for day.9Office of the Law Revision Counsel. 35 U.S. Code 154 – Contents and Term of Patent; Provisional Rights
The three-month clock runs from the Office Action’s mailing date, not from the original response deadline. If a two-month Office Action gets a one-month extension and a response filed in month three, no term is lost. Take a two-month extension and respond in month four, and about 30 days of patent term disappear. Take a five-month extension on a three-month Office Action and respond at the six-month mark, and roughly 90 days go.10eCFR. 37 CFR 1.704 – Reduction of Period of Adjustment of Patent Term
For pharmaceutical and other high-value patents, those days translate directly into revenue. Extra preparation time is not free even after the fee clears.
If the Deadline Passes Anyway
Miss the extended deadline and the application goes abandoned. Revival is possible under 37 CFR 1.137(a) if the abandonment was unintentional. The petition must be filed within two years of the abandonment date, along with the overdue response, the revival petition fee, and any unpaid extension fees.11United States Patent and Trademark Office. ePetition Filing Requirements: Petition for Revival of an Abandoned Patent Application Abandoned Unintentionally Revival costs more than an extension, takes longer, and can create intervening rights that weaken the resulting patent. Buying the right extension in time is always the cheaper play.