Update on the Public Disclosure and On-Sale Bar Doctrine: Secret Methods! Episode 146

Introduction to Public Disclosure and the On-Sale Bar

I usually don’t talk too much about individual cases on this podcast, but that’s exactly what I’m going to do today because there’s been some clarification in the law when it comes to public disclosures and the on-sale bar doctrine.

I’ve talked about this in a previous episode, but here’s a refresher: the reason you need to be careful about any public disclosures or sales of your invention is that if you disclose something publicly and there’s no patent application on file, then once it becomes public, you can’t get a patent on it anymore. You’ve essentially given up your patent rights, and the invention becomes part of the public domain.

The 12-Month Grace Period

There are a couple of exceptions. One is called the 12-month grace period, and it doesn’t apply everywhere in the world, but it does apply in the United States. The grace period allows you to file a patent application up to 12 months after you publicly disclose your invention.

So don’t come to me after your invention has been out in public for more than a year and expect to get a patent—it’s too late. There is another exception for experimental uses, but that rarely applies and is pretty strict.

Can a Public Disclosure Be Secret?

So, it sounds pretty simple—don’t publicly disclose your invention without a patent application on file. But sometimes there are gray areas. What if your public disclosure is actually… secret? Sounds like an oxymoron, but this was a real case.

The Samuel Barnes Corset Case

Picture it: it’s the mid-1800s, and Samuel Barnes is tinkering away, trying to make life a little more comfortable for all those corset-wearing folks. He comes up with a brand-new type of corset spring and shows it to his friend Elizabeth Lippmann. She’s impressed and starts using it right away. So far, so good, right?

Here’s where it gets interesting. Elizabeth used the spring in her corset for years—not in any public display, just privately enjoying its comfort under her clothes. But Samuel didn’t file for a patent until over a decade later.

You might think that because Elizabeth wasn’t showcasing the corset publicly, it wouldn’t count as public use. But the Supreme Court thought otherwise. They said, “Wait a minute, Samuel. Elizabeth used the spring without any secrecy or restriction? That’s public use!”

In other words, even though it was hidden under clothing, her ordinary use started the clock ticking on Samuel’s patent rights. Because he waited too long, he lost his ability to patent it.

The On-Sale Bar

Closely related to the public use doctrine is the on-sale bar. It’s essentially the same principle: if you sell or even offer to sell an invention and there’s no patent application on file, the clock starts ticking. In the U.S., you must file within 12 months of that date. Ideally, you should file before any sale or public use—especially if you’re interested in foreign protection. In some countries, if you sold the product even a day before filing, you may have already lost your rights.

Why Does the On-Sale Bar Exist?

Why do we have this rule at all? Why can’t someone just patent an invention after they’ve been using or selling it for a while?

The on-sale bar acts like a referee. It ensures inventors can’t game the system by profiting from an invention while delaying the patent filing. You don’t want a situation where someone watches you make money on a product for 10 years, then suddenly files a patent and tries to shut you down.

The rule forces a decision: either seek a patent early and share your invention with the public—or keep it as a trade secret and forgo patent protection.

What’s the Update? Secret Methods and the On-Sale Bar

So what’s new? It’s about whether secret processes—used to make publicly sold products—can trigger the on-sale bar.

The Coffee Example

Say you’ve invented the world’s smoothest coffee brew method, but you keep it a secret. You start selling the resulting coffee in hip cafés, but no one knows how it’s made. Can the on-sale bar apply to your secret method just because you sold the product made by it?

The Steak Example

Now imagine a chef who creates a revolutionary steak-aging process. He uses this method in his restaurant, but never tells anyone how it’s done. Customers just enjoy the delicious steaks. If the chef later tries to patent the aging process, does the on-sale bar block him?

The Software Example

Or consider a software developer with a cutting-edge algorithm. She integrates it into her product and sells it successfully—but keeps the algorithm confidential. Can she patent the algorithm after launching her product?

The Celanese v. ITC Decision

Well, the Federal Circuit just gave us an answer in the case of Celanese v. ITC. They held that even though the method was never publicly disclosed, selling the product made using the method does trigger the on-sale bar.

So once again, the courts are taking a broad view of what counts as “on sale.” Secret methods—if they are used to make a product that is sold—can start the patent clock, even if the method itself is kept secret.

International Differences

Now, I’m not a European patent attorney, but from what I’ve read, Europe is more lenient. In some cases, European patent law allows inventors to patent a process even after selling the product—provided the process isn’t obvious from the product itself.

But the U.S. is stricter, so depending on your situation, it may be possible to get a patent in Europe and not in the U.S.

Until next time, I’m Adam Diament—and keep on inventing!