Does a pitch deck, demo or conference talk count as public disclosure?

A conference talk almost always does; a pitch deck and a demo depend on who saw them and under what terms. The test for public disclosure is whether the invention was made available to at least one person who was free to pass it on. A talk, a published abstract, a poster, a recording online, a demo-day livestream or slides uploaded to a conference site are all public. A pitch to two investors who signed an NDA is not. A pitch to a room of investors who signed nothing is, in most jurisdictions, a public disclosure, even though most investors would never repeat it. Disclosure also has to be enabling: a slide saying you have a faster battery does not disclose the chemistry, but a demo that shows how it works, or a talk that explains the method, does.

Two details catch founders out. First, trade-show demos: the European Patent Convention's six-month exhibition exception (Article 55 EPC) only covers officially recognised international exhibitions, which in practice means world expos, not industry trade shows. Second, the US grace period covers your own disclosures but does nothing for Europe, where absolute novelty applies and there is no grace period. The safe sequence is to file a first application before the talk, the demo day or the pitch without an NDA, then present freely. If the disclosure has already happened, note the date, who was there and what exactly was shown; that record decides what is still patentable and where. Pasting the invention into a consumer AI assistant raises a related question: does that count as public disclosure?