Grace period – The much-loved novelty safety net

Article | 14 June 2021

Grace period – The much-loved novelty safety net

Grace period – The much-loved novelty safety net

In a perfect world, an inventor would have the time and the money to ensure that an invention is sufficiently developed and refined with a marketing strategy and future revenue streams in place before a provisional patent application is filed and the invention disclosed to the public.

If only reality was this easy.

Despite best intentions, commercial realities of developing and commercialising an invention often dictate that “shortcuts” must be taken – with finite budgets only so much that can be done in a timeframe. From a patenting perspective, some commercialisation shortcuts are ok, but others can be detrimental.

One requirement of patentability common around the world is that an invention, as defined by the patent claims, must be novel over the prior art base. The prior art base includes publicly available information such as patents, journal articles, videos such as on YouTube, images, and public acts. The novelty requirement is typically one of absolute novelty, which means that the invention cannot have been disclosed in a non-confidential and enabling manner in any way before the patent application is filed, even by the inventors themselves. There are varying degrees of what is considered an enabling disclosure of an invention, but any disclosure before filing a patent application has the potential of detrimental consequences for novelty.

So what happens if one of these shortcuts accidentally involves fully disclosing the invention before a patent application is filed? Fortunately, many countries have what is known as a “grace period” for such situations. A grace period allows a specific period of time extending from before the filing date of a patent application in which certain disclosures of an invention are disregarded for novelty. In short, a grace period has the potential to remove certain disclosures from the prior art base.

An issue with grace periods is that not all countries have them, and for those that do they are not always harmonised. It is therefore important to be aware of the limitations of grace periods between different countries. The following table provides a brief overview of applicable grace periods of some of the major jurisdictions most patent applicants consider filing in. The specifics of the grace period in each country is then explained in further detail below.

Overview of Grace Periods

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Australia provides a 12-month grace period so long as a complete application – such as a PCT application or standard patent application, but not a provisional patent application – is filed within 12 months of the disclosure. Compared with most other jurisdictions, the grace period in Australia is broad and generous and, in essence, covers any type of disclosure.


United States

The United States has a similar 12-month grace period regime to Australia. However, there is also an additional grace period provision in the US for situations where, if an inventor publicly discloses their invention prior to filing, the inventor’s disclosure “antedates” a third party’s disclosure of the invention made in the interim. However, this provision is somewhat limited because it is likely that the invention disclosed by the third party is limited to the same invention as that disclosed by the inventor.

South Korea

Similar to Australia, South Korea has a grace period extending from 12 months before the filing date of a complete application. However, two specific procedural conditions must be satisfied for the grace period to apply:

    1. When the disclosure was made by a person with a right to the disclosed invention.

      In this situation, the applicant should file a notice of publication exception along with evidence to the Korean Patent Office within 30 days from the complete filing date.

    2. When the disclosure was made not in accordance with the intent of the person having a right to the invention.

      In this situation, the grace period may be claimed during a response period during examination or within three months after receiving the notice of allowance.



Similar to Australia and the United States, the grace period in Canada can be used when a complete patent application is filed within 12 months of a public disclosure of the invention. However, recent changes to Canadian Patent law mean that there is more leeway given in circumstances when a disclosure occurs within two months after the filing a provisional patent application. In these circumstances, if the applicant misses the deadline to claim priority back to the provisional patent application, the grace period is extended to 14 months. This is good news for applicants, as it provides a welcome safety net to an otherwise immovable deadline that applicants must meet.



Japan has recently revised its Patent Act to extend the Japanese grace period from six months to twelve months between the initial disclosure and the filing of a complete application. However, unlike Australia and the United States, the applicant must actively apply for the grace period, which requires submissions of a grace period request at the time of filing the patent plus filing a proving document within 30 days of the filing date proving the disclosure is to be disregarded under the grace provision.


China and Europe

China and Europe each have a “grace period”, but it is very much limited. Inventions can be exhibited at certain recognised exhibitions, but the Applicant must obtain and file supporting documentation within a set time limit to support their claim to a six-month grace period. A six-month grace period is also available in the case of abusive disclosures by third parties of the invention.
In general, the situations where the “grace period” in China and Europe applies is very limited, which, in practice, essentially means that these countries do not have a grace period that applicants can reasonably rely on. Therefore, having to rely on grace periods to obtain patent protection in a number of countries is often met with considerable issues.

Final Thoughts

Although the grace period can “rescue” an invention from a novelty destroying disclosure, it is important to note other sources of information release with the disclosure of the invention may not necessarily be protected by the grace period. This has the potential to cause ramifications for later modifications or improvements of the invention.

It is far better to disclose an invention after filing a patent application than having to rely on the grace period, especially since not all countries have useful grace periods. However, should applicants find themselves in a situation where they need patent protection after disclosing their invention, the grace period may be used depending on the circumstances and the countries where protection is sought.

The availability of grace periods in different countries depends on the specific circumstances of the invention and disclosure.


Dr. Andreas Hartmann