At what point do conversations become prior art?



Is a conversation between two colleagues or a group in a lab meeting considered prior art? Neither are in a public forum. Is there an assumption of confidentiality?

MW Long

Posted 2018-01-29T18:21:58.793

Reputation: 51



This is a very interesting topic and a short answer is rather impossible. It's all about how you define the public and its access to prior art.

The EPO (Europe, for the most part of it) considers that "information is generally to be regarded as having been made public if even just one single member of the public is in a position to gain access to it and understand it, and if there is no obligation to maintain secrecy". What happens, though, in practice is that such guidelines driven by the case law is a dynamic set of rules which changes with time. Some examples are clear-cut cases and some are subject to new-created case law. For practice as per EPO you can read more here:

For the US I am not fully aware of the rules that regulate such issues, but there should be relevant case law there as well (who is "public", the concept of "secrecy"). Mind that in the US there is an exception, a one-year grace period, within which a disclosure made by the inventor or someone who got access to the information by the inventor, is not prejudicial in a patent application's novelty (US experts may correct me here, if I am wrong). This exception does not apply, though, in other jurisdictions, particularly the EPO, so "handle with care".


Posted 2018-01-29T18:21:58.793

Reputation: 1 576


I'm not a lawyer, but my understanding is that something has to be publicly disclosed to be considered prior art. Conversations between colleagues within the same business is clearly not prior art. What conversations with other employees does impact is inventorship. If someone contributes an idea that gets reflected in a patent's claims, then they probably should be considered a co-inventor.

Eric S

Posted 2018-01-29T18:21:58.793

Reputation: 7 963

Everything that "can be expected to be dispersed out of the control of the disclosing person" is prior art in germany (rough translation from Kaßer/Ann patent law (in german) p. 283) – DonQuiKong – 2018-01-30T07:05:11.723

(I agree with you, that's just an addition.) – DonQuiKong – 2018-01-30T07:13:15.243

@DonQuiKong Feel free to edit the answer. Try to put it in lay language. – Eric S – 2018-01-30T15:25:45.040

I was advised by several patent attorneys to be very careful about disclosing even casually in conversation prior to submitting a provisional. I suspect it's a fuzzy issue at this level, but legal minds need to "think paranoid", and this mental framework is often the basis of good legal advice (considering every potential problem that might arise, no matter how unlikely.) Your point about inventorship is a good one. – DukeZhou – 2018-02-02T20:05:18.223

1@DukeZhou Conversations with employees of the same business is how many patents are how most inventions happen. Confidentiality is a requirement of every business I've ever worked at. – Eric S – 2018-02-03T00:05:13.630

@EricShain Thanks for the clarification re: employees of the same business. I suspect it's a different situation for solo inventors, or discussing at conferences with people not in the same organization? – DukeZhou – 2018-02-05T22:53:46.363

1@DukeZhou Except for fellow employees, I wouldn’t discuss confidential info with anyone unless I had a formal confidentiality agreement in place. – Eric S – 2018-02-06T01:30:38.760