How do global time zones affect a patent’s priority?

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Birss J, in the Patents Court, recently had to consider the impact of global time zones on a patent’s priority.

The effect of the world’s time zones means that an act that is happening at the same moment in time may be happening on Monday 1 January in one country and Tuesday 2 January in another. This has implications for priority dates in the international patent regime.

In Unwired Planet International Ltd v Huawei Technologies Co Ltd and others [1] a patent had a priority date of 8 January 2008. The defendants were relying on prior art which had been uploaded on 8 January 2008 but which, because of the difference in time zones, was publicly available to and was downloaded by people in Western time zones on 7 January 2008. The defendants therefore asserted that the document relied on formed part of the state of the art as at 7 January 2008 and, as such, represented prior art on the patent’s 8 January date.

Birss J ruled that since, at any given moment, the dates and times around the world are different, a patent’s priority date had to be based on some frame of reference and the only one that made any sense was the date at the patent office in the jurisdiction at which the priority document was filed. A disclosure on the same day as the priority date, albeit earlier in time, was not prior at and a document disclosed on the internet on the same day as a patent’s priority document had been filed was not part of the prior art because, by the operation of different time zones, it was available in some parts of the world where the date was that of the previous day.

Accordingly, the document relied upon by the defendants was not part of the state of the art on 8 January 2008.


[1] [2015] EWHC 3366 (Pat)