Key Takeaways

  • Expired patents become public domain, allowing anyone to use or build upon the original invention.
  • Some expired patents can be reinstated under specific conditions by paying USPTO fees.
  • Businesses and patent investors can legally exploit expired patents to develop products, improve innovation, or initiate licensing.
  • Knowing the causes and categories of patent expiration (abandonment vs. term expiration) is critical for evaluating purchase opportunities.
  • While the cost of expired patents is low, risks such as enforceability and infringement litigation must be considered.
  • You can search expired patents through USPTO and other free databases, but verifying the actual status with legal help is advised.

Expired patents for sale are available 20 years from the day the patents were filed. Once expired, it leaves the patent open for others to replicate it without breaking any laws. Patents also expire because the inventors are not consistent in the payment process, and the patent is considered abandoned and eligible for sale.

Benefits of Expired Patents for Sale

  • Patents that have expired after the 4-, 8-, and 12-year mark may be reinstated by the USPTO by paying hefty fees and/or providing valid excuses.
  • Fees that are technically due prior to the scheduled 3.5, 7.5, and 11.5 years are eligible to be paid within the six-month grace period if the patent owner pays a $150 fee, which must be submitted with the renewal fees.
  • When someone purchases an expired patent, it is less work for the buyer, as all work has already been completed by the previous owner. This allows the new owner to focus on improving the quality and functionality of the invention.
  • Unlike the utility patent, plant and design patents do not expire until 14 years from their file dates. Neither patent requires maintenance fees.

Why Do Patents Expire and What Happens Next?

Patents can expire for several reasons:

  • End of statutory term: Utility patents expire 20 years from the filing date, while design patents last 15 years from grant. Once expired, the invention becomes public domain.
  • Failure to pay maintenance fees: Utility patents require maintenance fees at 3.5, 7.5, and 11.5 years. If not paid, the patent can lapse before the 20-year mark.
  • Non-renewal of international patents: Many jurisdictions require annual renewals. Non-payment often results in earlier expiration than in the U.S.

Once a patent expires, it means:

  • The invention is no longer protected under patent law.
  • Others can freely use, make, or sell the invention without infringement concerns.
  • It may be re-registered or modified into a new patent if substantial innovation is added.

Cons of Expired Patents for Sale

  • If maintenance fees are ignored and not paid to the USPTO after the designated amount of time of 4, 8, and 12 years, a utility patent will expire.
  • Old patents that have expired tend to attract legal situations and lawsuits.
  • Expiring patents can end up in court as infringement claims.
  • Businesses and corporations sometimes turn a profit by buying old patents and then suing for infringement.
  • Be aware that as a patent moves through the E1, E2, and E3 tranches, the fees will increase.

Steps for Searching Expired Patents for Sale

  • The first step is to do a patent search.
  • Google Patents Advanced Search is a viable option.
  • Make a note of the publication number and the patent number for those you are interested in.
  • Use the free database search for expired patents at the United States Patent and Trademark Office.
  • Search the database using the publication number or the patent number.
  • Look for the patent's status. If it is active, it will show Patented, Expired, or Abandon.
  • Consult with a patent attorney before assuming a patent is abandoned or expired.

How to Confirm a Patent's Expiration Status

Even if a patent appears expired, it's essential to confirm its legal status to avoid future infringement issues. Follow these steps:

  1. Search the USPTO Public PAIR system to view legal status, maintenance fee history, and expiration due to non-payment.
  2. Use the USPTO Patent Maintenance Fees Storefront to see if a fee has lapsed or been paid within the six-month grace period.
  3. Verify abandonment vs. expiration—abandoned patents (from non-payment or procedural failure) can be reinstated under certain conditions.
  4. Check the global status for international patents via WIPO’s PATENTSCOPE or the EPO Espacenet platform.

Working with a patent attorney helps interpret whether an expired or abandoned patent is still enforceable or viable for reuse.

Buyers of Expiring Patents See Profit in Infringement Claims

Patents can end up in the hands of speculators, and they might go to court with infringement claims versus other companies in an effort of a large payoff. This might be by going to trial or from forcing settlements. Some of the most prolific suers in the country can find new life in patents that are close to the end of a 20-year term or patents that have lapsed. Sometimes, the buyers of older patents are firms that turn to sue for infringement or licensing them a business.

Half of the patents from lawsuits are from licensing firms in the 1990s, while the rest are from the early 2000s. Examples of businesses that sold patents that ended up being used later in litigation are Cypress Semiconductor Corp., Xerox, General Electric Co., and Boston Scientific Corp.

Xerox only represents a small portion of companies that transferred or sold patents that turned into lawsuits. Many of the businesses that sold patents to licensing firms so other companies could be sued ended up being the targets of similar lawsuits. The federal government has made it harder on some patent litigants.

There have been dozens of patents that judges threw out since June 2014, when the Supreme Court set a new test to see if software covers more than a single concept. Many others have been challenged successfully at the patent office.

As of Dec. 1, 2015, a patent owner is required to submit substantial details when filing a lawsuit. The week before this went into effect, over 500 lawsuits were filed, and all but one patent went back to ideas from the 1990s. It's thought that many patents from that time period were overbroad and very broad. eDekka LLC, the most prolific suer of 2014, ended up filing over 200 lawsuits against website operators and retailers that were using shopping carts on their sites. This patent was first sought back in 1992.

Other Ways to Profit from Expired Patents

Beyond litigation and licensing, expired patents can offer strategic business opportunities:

  • Product Development: Use expired technologies to develop cost-effective products without licensing fees.
  • Reverse Engineering: Improve upon old inventions by identifying weaknesses and integrating modern technology.
  • Patent Landscaping: Analyze expired patents in your industry to identify trends, gaps, or ideas for innovation.
  • Educational Tools: Academic institutions and startups often use expired patents as teaching materials or for R&D.
  • Open Innovation: Companies can leverage expired patents for open-source projects or internal development pipelines.

These strategies are particularly attractive for small businesses and entrepreneurs who lack the capital to license newer technologies.

Amazon's Multi-billion Dollar Patent Expired In 2017

Amazon 1-Click has made the company a large amount of money since it came out. Amazon applied for the patent in 1997, and they were granted the patent in 1999. The basis of the proposition is that when you store your address and payment information, you'll only need to click one button to buy items. This means you'll have fewer steps to ordering overall, which takes less time and is known as frictionless.

It was suggested that the 1-Click business may be worth close to the $2.4 billion that Amazon is. While it's undeniable that there's an advantage to ordering something quickly, the primary advantage is forming an experience that isn't easily found on any other online store.

However, there is an exception to this, which is Apple. They use their own version of this system and pays a sum of money that's undisclosed in order to do this. Many users will notice that the app store has a very similar ordering system, as it's easy and quick. If you had to take the time to add apps to the cart first and then check out, it would most likely decrease sales. This proves Amazon's point regarding this system.

That said, the path for 1-Click isn't completely clear. The European Union will not grant Amazon a patent for it. They defined the technology as reliant on previous art and too obvious. The argument was mainly around the fact that Amazon is only setting cookies, which any retailer could do and produce identical results. Canada originally wouldn't issue a patent to Amazon for their 1-Click feature, but a legal battle was fought and the patent ended up being issued in 2011. Due to this, Canada redid their guidelines regarding patent applications.

Europe and Canada weren't the only ones who didn't think Amazon's patent was justified, as Australia rejected the claim as well over several points. It's certain that Amazon would like to keep their patent, but it's unlikely to have a huge impact like it might have in the past. The company is now known for selling a large range of products and delivering them quickly.

1-Click was a great idea when it came out, but Amazon now has a large amount of brand loyalty that's been built up. Most people won't shop at another store even if they had a single button to purchase items. Amazon is also thinking of bigger ideas on a constant basis that will bring in higher profits in the coming years.

Patent Expiration Timeline

In the United States, utility patents generally expire 20 years from their filing date. Design patents, by contrast, expire 15 years from the date of issuance. Once a patent expires, the invention enters the public domain, allowing others to use or reproduce it freely without infringing the original rights.

Understanding Patent Tranches

Patent expiration is also monitored through a system of maintenance periods called tranches. These are categorized as E1, E2, and E3. Each tranche represents a specific window during which maintenance fees must be paid to keep a utility patent active.

  • E1 Tranche: Occurs at 3.5 years
  • E2 Tranche: Occurs at 7.5 years
  • E3 Tranche: Occurs at 11.5 years

If fees are not paid during these periods (plus the allowed grace period), the patent may lapse before the 20-year expiration term.

Maintenance Fees and Rolling Expiration

Maintenance fees increase with each tranche. After paying the E1 fee, the patent transitions into the E2 tranche, extending the patent’s rolling expiration date by four additional years. This rolling system continues until the E3 payment is made. Once the E3 maintenance fee is paid, the patent remains valid until the end of its full term.

How the Rolling Expiration Field Works

The rolling expiration date is a useful reference for tracking the lifecycle of a patent. It can help identify patents that are:

  • Due for renewal
  • Within the six-month grace period after a missed payment
  • Officially expired

This information is critical when evaluating expired patents for sale, as it clarifies whether a patent has truly lapsed or if it may still be revived.

The Role of Patent Attorneys in Evaluating Expired Patents

Before purchasing or using an expired patent, it is highly recommended to consult a qualified patent attorney. Although a patent may appear expired, there could be related patents, continuations, or foreign protections still in force. A legal expert can help determine if the technology is truly available for free use or acquisition.

Frequently Asked Questions

What is the difference between an expired and abandoned patent?An expired patent has reached the end of its term or was not renewed. An abandoned patent lapsed due to failure in meeting USPTO requirements but might still be reinstated.

Can I patent something based on an expired patent?Yes, but only if you add novel, non-obvious improvements. You cannot re-patent the original invention as-is.

Is it risky to commercialize an invention from an expired patent?There can be risks if related patents (like continuations or improvements) are still active. Legal due diligence is crucial.

Are design patents included when searching expired patents for sale?Yes. Design patents also expire, typically 15 years after issuance, and can be reused if the design is unprotected elsewhere.

Can expired patents be used for international manufacturing?Possibly. But ensure the patent is also expired in the manufacturing country. Patent laws vary by jurisdiction.

If you need help with expired patents for sale or the patent application process, you can post your legal need on UpCounsel's marketplace. UpCounsel accepts only the top 5 percent of lawyers to its site. Lawyers on UpCounsel come from law schools such as Harvard Law and Yale Law and average 14 years of legal experience, including work with or on behalf of companies like Google, Menlo Ventures, and Airbnb.