How Does a Priority Date Work?

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A priority date is set early in the patent application process as the initial date of filing. It is important because it determines where your application stands among the prior art base. This article outlines the basics on how to secure a priority date for your application.

When Are Priority Dates Important?

In the invention process, it is common to have variations in design before you have a final product. As new ideas evolve, the ‘final’ design may no longer be the end goal. As inventors go through this creative process, it is essential that the initial idea is protected with a priority date. Protection is especially necessary when the initial invention is public. It ensures that you have priority over other inventors building on your innovation to make similar modifications as you. This is because the new inventor’s application is assessable on the earliest date of their filed application. As any improvements to your product must have come after your initial filing date, their application will be rejected. This is in contrast to your parent application (initial invention) which will have your initial filing date as the priority date in accordance with section 43 the Patents Act 1900 (Cth).

When Does the Priority Date Make a Difference?

Only certain types of applications can benefit from the priority date. For two inventions that do not have a connection, you will need to lodge separate applications for each. The second application will not come under an earlier priority date. However when the second application is in fact from the same family of patents as the first, you can claim the priority date of the second application to be the same date as the first application. It is important to note that priority dates do not last forever, and there are time limits you need to be aware of.

Overseas Patents

Priority dates are also useful for patents you may want to register in a different country. If you would like to protect those ideas overseas, the initial filing date may apply as the priority date. It is useful to secure the priority date while figuring out whether your patent is worthwhile to pursue in the new country.

If you are unsure whether a priority date applies to an innovation, or if you think someone else’s invention may have a priority date that affects you, contact a Patent Lawyer.

Have more questions? Contact a LawPath consultant on 1800 529 728 to learn more about customising legal documents and obtaining a fixed-fee quote from Australia’s largest legal marketplace.

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