Every patent has an end date. For a U.S. utility patent, that day comes 20 years from the application’s earliest effective filing date, assuming maintenance fees have been paid and no term adjustments apply. When that date arrives, the exclusive rights the patent granted disappear, and the invention it covered becomes freely available to anyone.
Understanding what that transition looks like, and what options exist before it happens, is important for anyone managing a patent or building a business around one. At Goldstein Patent Law, we help clients plan ahead for expiry rather than react to it.
The 20-Year Patent Term
The term of a U.S. utility patent is 20 years from the earliest effective filing date of the application under 35 U.S.C. § 154. That is the filing date, not the grant date. Since patents are typically granted two to three years after filing, most patents effectively provide somewhere between 17 and 18 years of protection from the time they actually issue.
A design patent, by contrast, lasts 15 years from its grant date. A plant patent lasts 20 years from its filing date, the same as a utility patent, but is not subject to maintenance fees. Our post on plant patents covers the rules specific to that category.
The expiry date is calculated from the filing date, not the priority date of a related provisional application. Filing a provisional does not start the 20-year clock. That clock starts on the filing date of the nonprovisional application that ultimately becomes the patent.
Patent Term Adjustment: When Your Patent Lasts Longer Than 20 Years
The 20-year rule is the baseline. The actual expiry date of a specific patent may be later than that baseline because of patent term adjustment, or PTA.
PTA exists because the patent application process takes time, and some of that time is caused by USPTO delays rather than anything the applicant did. Under 35 U.S.C. § 154(b), the USPTO is required to compensate patent holders for certain delays in examination. The formula is: USPTO delay minus applicant delay equals patent term adjustment. If the office took longer than it should have to act on your application, those days are added to the back end of your patent’s term.
PTA applies automatically. The USPTO prints the total PTA in days on the front page of every issued patent. An applicant who takes unusually long to respond to Office Actions will see their PTA reduced, as those delays are subtracted from the calculation.
The practical effect is meaningful. By late 2025, the average PTA across all utility patents had rebounded to approximately 296 days, meaning the typical patent was expiring roughly ten months later than its nominal 20-year term. For patents in heavily backlogged technology areas, the adjustment can be considerably larger.
PTA does not affect the maintenance fee schedule. Those fees remain due at 3.5, 7.5, and 11.5 years after grant regardless of any term adjustment. And PTA is distinct from the surcharge-and-lapse rules that apply when maintenance fees are missed, which we cover separately in our post on patent maintenance fees.
Patent Term Extension: A Narrow Exception for Regulated Industries
A separate mechanism, patent term extension under 35 U.S.C. § 156, allows the term of certain patents to be extended beyond their normal expiry date. This applies specifically to patents covering products that required regulatory review and approval before they could be sold, most commonly pharmaceutical drugs and medical devices that went through the FDA approval process.
The rationale is that a patent holder who spends years waiting for FDA approval cannot commercially exploit the patent during that waiting period. PTE compensates for that lost time by extending the patent’s term after the product is approved.
The extension is capped at five years and cannot push the total effective patent term past 14 years from the date of regulatory approval. Only one patent per product can receive a PTE, and the application must be filed within 60 days of receiving regulatory approval.
PTE is a pharmaceutical and medical device tool, not a general-purpose extension mechanism. If your patent does not cover a product that required regulatory review by the FDA, another federal agency, or a foreign regulatory body recognized under the statute, PTE does not apply.
What Expiry Means Legally
When a patent expires, every right it granted disappears simultaneously. There is no partial expiry, no grace period, and no notification requirement. On the day the patent expires:
The exclusive right to make the invention ends. Anyone can manufacture the previously patented product without permission.
The exclusive right to use the invention ends. Third parties can operate processes or systems that were covered by the patent without a license.
The exclusive right to sell and offer to sell the invention ends. Competitors can market and sell the product freely.
The exclusive right to import the invention ends. Foreign manufacturers can import the product into the United States without restriction.
Any licenses tied to the patent that do not have separate contractual provisions survive on their own terms, but the underlying patent rights they were built on are gone. Royalty obligations under patent licenses generally cease at expiry unless the license agreement specifies otherwise, a point the Supreme Court addressed in Kimble v. Marvel Entertainment (2015), which held that a licensee need not pay royalties on a patent after it expires.
The Public Domain: What It Means in Practice
When a patent expires, the invention it covered enters the public domain. That phrase means something specific: the technology described in the patent specification is free for anyone to use, reproduce, build on, or commercialize without asking permission or paying royalties.
This is by design. The patent system is a bargain between inventors and the public. In exchange for publicly disclosing how the invention works, the inventor gets a limited period of exclusivity. When that period ends, the public gets the full benefit of the disclosure.
The most visible example of this is the pharmaceutical industry. When a drug patent expires, generic manufacturers can enter the market and produce the same compound at lower prices. The original manufacturer can no longer prevent them. This is exactly what the system was designed to produce.
In other industries, the transition is less dramatic but equally real. The expiry of a foundational software algorithm patent, a manufacturing process patent, or a product design patent opens that technology to every competitor who previously had to work around it or pay to license it.
For inventors whose patents are approaching expiry, the strategic question is how to maintain competitive advantage through other means once the patent protection is gone.
What Doesn’t Expire When Your Patent Does
Patent expiry does not mean the end of all IP protection. Other forms of intellectual property survive and remain fully enforceable after a patent expires.
Trademarks do not expire as long as they are used in commerce and properly maintained. The brand identity you built around your patented product remains yours. Competitors can make the same product after your patent expires, but they cannot sell it under your brand name or with your logo. Our post on the difference between patent and trademark explains how these two protections work together.
Trade secrets remain protected for as long as they remain secret. The manufacturing know-how, process optimizations, and formulation details that you never disclosed in your patent specification remain yours. A competitor can make a product that falls within your expired patent claims, but they cannot access the specific production methods you kept confidential unless they develop them independently.
Copyright in any original software code, documentation, or creative materials associated with the invention remains in force for the life of the author plus 70 years.
Continuing brand equity and customer relationships are not IP rights, but they are real competitive advantages that patent expiry does not touch.
For many companies, the strategy near patent expiry involves leaning into these remaining protections while building the next generation of patent-protected innovations.
Continuation Strategy: Extending Your Protection Before Expiry
One of the most important things to understand about patent expiry is that it does not have to be the end of protection for a product line. A continuation application allows you to file a new patent application claiming priority to the same original application, covering aspects of the invention that were not claimed in the original patent.
Continuation applications must be filed while the parent application or patent is still active. Once a patent expires, the window to file continuations from it is closed. This is why reviewing your patent portfolio in the years before key patents expire is so valuable.
Improvements and refinements you have made to the original invention since the patent was filed may support new, patentable claims in a continuation or a separate improvement patent. Our post on patenting improvements to existing products covers how this works and what the scope of protection looks like when you build on your own earlier work.
Companies that manage their patent portfolios proactively use continuation strategy to maintain layered protection on important product lines well beyond the life of the original patent.
Two Ways a Patent Ends Early
It is worth distinguishing natural expiry from two other ways a utility patent can end before its full term runs.
Lapse for non-payment of maintenance fees occurs when a patent holder misses one of the three required maintenance payments at 3.5, 7.5, or 11.5 years after grant and does not pay during the six-month grace period. The patent lapses and becomes unenforceable. Unlike natural expiry, a lapsed patent may be revivable through a petition to the USPTO if the delay was unintentional. Our dedicated post on patent maintenance fees covers the full fee schedule, grace periods, and revival process.
Invalidation through litigation or post-grant proceedings can end a patent’s life before expiry if a court or the Patent Trial and Appeal Board (PTAB) finds that the patent should not have been granted. An invalidated patent is treated as if it never existed.
Natural expiry at the end of the 20-year term is different from both. It is the intended, predictable end of a patent’s life, and it requires no action by any third party.
How to Find a Patent’s Expiry Date
Calculating the exact expiry date of a utility patent involves several steps. The starting point is the earliest effective filing date, which is usually the filing date of the nonprovisional application. To that date you add 20 years, then add any patent term adjustment shown on the face of the patent. If a terminal disclaimer was filed during prosecution, it may shorten the term to the expiry date of a related patent.
You can look up the status, filing history, and PTA of any U.S. patent through the USPTO’s Patent Center using the patent number. The Patent Center’s patent term information section shows the calculated expiry date directly, which is faster than working through the arithmetic manually.
Google Patents also displays estimated expiry dates, though these should be verified against the USPTO’s own records for important decisions.
Frequently Asked Questions
Can a U.S. patent be renewed after it expires?
No. Unlike trademarks, patents cannot be renewed after they expire. Once a utility patent’s 20-year term ends, the rights it granted are permanently extinguished and the invention enters the public domain. The only mechanisms to extend a patent’s term are PTA, which is calculated automatically during prosecution, and PTE, which applies only to patents covering products that went through federal regulatory review.
Does patent expiry happen automatically, or does the USPTO notify the holder?
Expiry is automatic. The USPTO does not send a notification when a patent expires. The responsibility to track expiry dates falls on the patent holder and their legal counsel. For portfolios with multiple patents, this is one of the core functions of patent docketing.
Can competitors start selling my product the day my patent expires?
Yes. As of the expiry date, all exclusionary rights under the patent are gone. There is no notice period or transition window. Competitors are free to manufacture, use, and sell the previously protected invention from the date of expiry forward.
If a patent expires, does the patent specification become public?
The patent specification was already public. Patent applications are published by the USPTO 18 months after the earliest effective filing date, long before the patent expires. Expiry does not change what is disclosed; it changes who can legally use that disclosure.
What happens to my licenses when my patent expires?
License agreements should be reviewed individually, as their terms vary. As a general rule, patent royalty obligations end at patent expiry unless the license agreement specifically provides otherwise. Post-expiry royalty provisions are generally unenforceable following the Supreme Court’s ruling in Kimble v. Marvel Entertainment (2015). If your licensing arrangements are tied to expiring patents, reviewing those agreements in advance of expiry is advisable.
Planning for What Comes After
Patent expiry is a known event on a known date, which means it can be planned for. The companies that navigate it best are the ones that started building their next layer of protection before the first one ran out, using continuations, improvement patents, trade secrets, and brand equity to maintain competitive advantage.
Contact Goldstein Patent Law to talk through your portfolio and what comes next. Whether you have years until expiry or months, there are usually options worth pursuing before that date arrives.
