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Public disclosure and offers for sale in the US and Canada

Disclaimer: The information provided in this factsheet is meant as an educational resource only and should not be construed as legal advice.

  1. Inventions must be novel (new) to be eligible for patent protection. In the US, an invention is no longer novel when it:
    • can be found in a printed publication anywhere in the world
    • is in public use
    • is offered for sale

One should be aware that any public disclosures, such as an inadvertent disclosure, and offers for sale relating to your invention might exclude your invention from the novelty requirement.

  1. What is public disclosure?
    • A public disclosure is any non-confidential communication made by an inventor or an invention owner to one or more members of the public about their invention.
    • A public disclosure reveals the existence of the invention and enables an appropriately experienced individual ("person having ordinary skill in the art") to reproduce the invention. 
  2. When should you publicly disclose your invention?
    • When working on an innovative product or services, it is often tempting or necessary to discuss it with a 3rd party to test the market requirements or to get funding.
    • If a patent application or provisional patent application is not filed before these discussions happen, and unless these discussions are done under a comprehensive NDA, the discussion will be considered a public disclosure that will void the novelty requirement of a patent application, in most countries.
    • Unless disclosure is done under an NDA, it should wait until after a patent is filed. In the US and Canada, there is a 12-month grace period applying to your public disclosure.
  3. Non-disclosure agreements (NDAs)
    • NDAs are useful to prevent public disclosures in the early stages, but in the US, a sale or offer for sale can block you from obtaining patent protection for your invention even if done under NDA.
  4. What is an offer for sale?
    • In a qualifying “offer for sale”, the other party must simply show acceptance to create a binding contract. If they are negotiating or if there are key details missing from the “offer to sell” it may not be an offer to sell.
    • For example, if the price has not been settled and is not in the “offer”, it might not qualify. The goods subject to the offer for sale do not need to be “on hand” or transferred at the time of the sale or offer.
  5. Non-confidential communication
    • A “printed publication” can be virtual, or in some case verbal as long as it is considered to have been made available to the public (either intentionally or unintentionally)
    • Other forms of non-confidential communication can include:
      • an academic poster
      • presentation to a symposium/conference
      • presentation to an investor
      • website article
      • book chapter
      • academic journal article
      • unguarded conversation in an airport
  6. How much is too much detail?
    • A public disclosure describes an invention in enough details such that someone familiar in the field (referred to as someone skilled-in-the-art) could duplicate the invention or put it to use.
    • If an invention is considered ready for patenting than an offer of sale could prevent you from securing a patent.
      • The invention is considered ready for patenting if:
        1. There is a formation of an invention beyond the conception thereof.
        2. The inventor has prepared drawings or other descriptions of the invention that are specific enough to allow a person skilled in the art to practice the invention.
        3. The invention is close to completion of the invention at the time of the offer and has demonstrated a high likelihood that the invention will work for its intended purpose on completion.
        4. You can be precluded from obtaining a patent if the invention is “on sale” before the effective filing date. An invention is considered on sale even if the details of the invention have not been made available to the public.
  7. Grace period
    • In the US and Canada, there is a 12-month grace period that applies to your own public disclosure. This means that you can discuss your inventions, show, your product containing the invention for up to 12 months before filing a patent application and your disclosure will not be used against it during the patent prosecution process. It is currently unclear whether this grace period also applies for offers for sale.
    • It is important to understand that there are few countries allowing this grace period and if protection is sought in other countries such as Europe or Asia, there is no grace period- a patent application must be filed BEFORE any type of public disclosure.
  8. Delaying your application
    • If you are counting on the grace period to delay the application, you must consider the risk that a third party who has been privy to the invention details not under NDA, may file a patent application before you do.
    • The new rule in the US is first to file, not first to invent. Should you decide to file at a later time, you may be rejected for patent protection because the third party filed a patent application for the invention first.

Example 1: You have invented a novel method for processing heart rate data to derive someone’s actual age and weight. You discuss the idea with friends in a restaurant without NDA. One of your friends decides to file a patent application with all the details you provided including additional details he thought of. When you file your application a few months later, the patent examiner will cite your friend’s application as prior art denying the allowance of your application. You now have to fight with the patent office to claim that your friend was not the inventor of this idea. This fight can end up costing you a lot of time and money.

If you really had to tell your friends about your idea, you should limit your discussion to what the invention does (deriving age from heart rate), without explaining how you derive the age from the HR. In that case, your friends will not have enough information to file a patent application before you do, unless of course, one of your friends is an expert in this field and you gave him enough information to figure out how to invent the method himself.

  1. Risks of early disclosure
    • You may think that the examiner is unlikely to find these public disclosures or offers for sale during prosecution.
    • If the patent is allowed then issued, even in light of the public disclosure or offer for sale, this can give a false sense of protection.
    • It is often when one tries to assert a patent that these early disclosures or offers for sale come to attack the patentability, which can possibly invalidate the issued patent.

Key considerations for Canadian companies:

Additional information:

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