Did showing, selling or crowdfunding your invention destroy your patent rights?

The statute is short enough to read. 35 U.S.C. § 102(a)(1) provides that a person is entitled to a patent unless "the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention". That is five independent triggers, and one is enough. Nothing in the sentence asks whether the disclosure was deliberate, whether it was commercially significant, or whether it was made by you.

What the bar is actually measuring

Two definitions do most of the work. The effective filing date is defined in § 100(i) as the actual filing date of the application containing the claim, or the earliest date the application is entitled to as a right of priority or benefit under §§ 119, 120, 121, 365 or 386. So a provisional application moves the date backwards for whatever it supports — which is the entire reason a provisional is worth filing early rather than well.

The second is geography, and the America Invents Act removed it. The Office states that public-use rejections under § 102(a)(1) may be based on uses that are public anywhere in the world, and that on-sale rejections may be based on sales or offers for sale without regard to where the sale activity took place. A demonstration in Shenzhen and a demonstration in Ohio now count identically.

The grace period is a United States rule, and that is the expensive part

Article 54(2) of the European Patent Convention defines the state of the art as "everything made available to the public by means of a written or oral description, by use, or in any other way, before the date of filing of the European patent application". There is no carve-out for the applicant's own disclosure. Article 55 gives the only relief, and it is not a grace period in any useful sense: six months, and only where the disclosure was due to an evident abuse against the applicant, or to display at an official or officially recognised international exhibition under the 1928 Paris exhibitions convention, with a certificate filed at the time of application.

Which means the order of operations decides everything. File first, and the Paris Convention does the rest: Article 4 gives twelve months of priority for patents, and Article 4B provides that a later filing in another member state "shall not be invalidated by reason of any acts accomplished in the interval, in particular, another filing, the publication or exploitation of the invention". Disclose first, and you have kept at most the United States.

"On sale" does not need a sale, and since 2019 does not need a disclosure

This is the limb that catches people who were careful about everything else. The test comes from Pfaff v. Wells Electronics (1998) and is applied by the Office in two parts: the claimed invention must have been the subject of a commercial sale or offer for sale, not primarily for experimental purposes, and it must have been ready for patenting. An offer nobody accepted still satisfies the first part. A quotation that a customer could have turned into a binding contract by saying yes is an offer; a general advertisement usually is not.

The counterintuitive half arrived in Helsinn Healthcare S.A. v. Teva Pharmaceuticals USA, Inc., 586 U.S. 123 (2019). Helsinn had signed distribution agreements covering a specific dose of its drug, under terms requiring the counterparty to keep proprietary information confidential, more than a year before it filed. A unanimous Court held that "a commercial sale to a third party who is required to keep the invention confidential may place the invention 'on sale' under § 102(a)". Congress had reused settled statutory language, and the new catchall "otherwise available to the public" merely "captures material that does not fit neatly into the statute's enumerated categories" rather than narrowing the words in front of it.

What the grace period forgives, and who it forgives it for

Section 102(b)(1)(A) is the whole of the relief most inventors are relying on. Disclosures made one year or less before the effective filing date are not prior art under § 102(a)(1) if "the disclosure was made by the inventor or joint inventor or by another who obtained the subject matter disclosed directly or indirectly from the inventor or a joint inventor". Read the second half slowly. The exception is about the origin of the disclosure, not about its harmlessness. A journalist who wrote about your demo is covered because the subject matter came from you. A competitor who reached the same design independently is not.

Subparagraph (B) adds a shield with a sharp edge. Once you have publicly disclosed the subject matter, a later disclosure of that same subject matter by anyone else is also removed from prior art. The Office is clear that this only covers the same subject matter: where an intervening disclosure adds an element you never disclosed, that element remains available as prior art against you. Publishing first buys protection for exactly what you published and not one feature more.

The five situations people are actually asking about

The experimental-use qualifier in the Pfaff test is narrower than its name suggests: the sale or offer must not be primarily for experimental purposes, which is a question about the objective purpose of the activity rather than about whether you personally learned something from it. Selling units to see whether people will buy is market testing, not experimentation.

An NDA keeps a conversation out of "available to the public"

A disclosure made under a genuine obligation of confidence is generally not a public use or a public availability at all, which is why the Office frames the public-use enquiry around a showing made under no limitation, restriction or obligation of confidentiality. That is the practical answer for the conversations you cannot avoid before filing: investors, contract manufacturers, a machine shop, a co-founder you have not yet signed. A mutual or one-way NDA is the difference between a private meeting and a § 102(a)(1) event.

It is not a universal solvent, and Helsinn is the proof. Confidentiality answers the disclosure limbs; it does not answer "on sale". A non-disclosure agreement attached to a supply arrangement keeps the design secret and still leaves the commercial offer sitting in the prior art. If the meeting is about buying and selling rather than about evaluating, the NDA is not the document doing the work.

The same instinct protects the fallback position. Anything you decide not to claim can remain a trade secret only for as long as it stays secret, and a disclosure that started a patent clock usually ended the trade secret at the same moment. Where the invention moves between entities — a spin-out, a licence, a technology transfer — make sure the contributors have signed an IP assignment before anyone relies on the priority date.

If it has already happened

The date is the asset now, and it is the thing most often reconstructed badly a year later. Establish it while the evidence is live rather than from memory in a deposition.

One more thing worth knowing before the panic sets in: a disclosure only bars what it disclosed. Section 102 is applied claim by claim. A campaign page that showed a finished housing may say nothing about the mechanism inside it, and a paper describing a result may not enable the method that produced it. The question is never "did I disclose the product" but "does the disclosure describe this claim".

What starts a clock and what ends a right

The grace period is not permission. It is a repair mechanism with a fixed expiry, available only for disclosures that trace back to you, and available only in one country. Treated as permission — as a year in which to launch, exhibit and take orders while deciding whether patents are worth it — it reliably converts a filing decision into a filing deadline nobody wrote down.

Which reduces to a single ordering rule that costs nothing to follow. The filing date is the only date that is fully within your control, and every other date in this article is measured against it. Move it earlier than the first conversation you cannot take back, and none of the rest of this applies.