Priority document

In patent, industrial design rights and trademark laws, a priority right or right of priority is a time-limited right, triggered by the first filing of an application for a patent, an industrial design or a trademark respectively. The priority right allows the claimant to file a subsequent application in another country for the same invention, design, or trademark effective as of the date of filing the first application. When filing the subsequent application, the applicant must claim the priority of the first application in order to make use of the right of priority. The right of priority belongs to the applicant or his successor in title.

The period of priority, i.e., the period during which the priority right exists, is usually 6 months for industrial designs and trademarks and 12 months for patents and utility models. The period of priority is often referred to as the priority year for patents and utility models.

In patent law, when a priority is validly claimed, the date of filing of the first application, called the priority date, is considered to be the effective date of filing for the examination of novelty and inventive step or non-obviousness for the subsequent application claiming the priority of the first application. In other words, the prior art which is taken into account for examining the novelty and inventive step or non-obviousness of the invention claimed in the subsequent application would not be everything made available to the public before the filing date (of the subsequent application) but everything made available to the public before the priority date, i.e. the date of filing of the first application.

The "basic purpose [of the right of priority] is to safeguard, for a limited period, the interests of a patent applicant in his endeavour to obtain international protection for his invention, thereby alleviating the negative consequences of the principle of territoriality in patent law."

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Wikipedia