Priority date
Also called right of priority, priority claim, Paris Convention priority, convention priority, claiming priority
Priority date is the filing date of the earliest application whose priority is claimed in a later application, or the later application's own filing date if no priority is claimed. The Patent Cooperation Treaty defines it this way for computing time limits2.
The right to claim priority comes from Article 4 of the Paris Convention. A later application filed in another member country within the priority period, twelve months for patents and utility models, is not invalidated by acts in the interval, such as another filing or publication of the invention1.
How a priority claim works
- A first application is filedAnyone who has duly filed a patent or utility model application in a Paris Convention country, or that person's successor in title, enjoys a right of priority for filing in the other countries. Any filing adequate to establish a filing date counts, whatever its later fate (Article 4A)1.
- Later applications are filed within the periodThe priority period is twelve months for patents and utility models and six months for industrial designs and trademarks. It runs from the filing date of the first application, and the day of filing is not included (Article 4C)1.
- Priority is declaredThe applicant declares the date and country of the earlier filing. Each country sets the latest date for the declaration and may require a copy of the earlier application (Article 4D)1.
- Acts in the interval do not count against itA later filing within the period is not invalidated by acts in the interval, in particular another filing or the publication or exploitation of the invention (Article 4B)1.
What the priority date decides, and what it does not
| Decided by the priority date | Not decided by the priority date |
|---|---|
| Which earlier disclosures count as state of the art for novelty, under Article 54(2) and (3) EPC7,8 | The patent term: patents obtained with priority have the same duration as without it (Paris Convention Article 4bis(5))1 |
| Who is entitled to the European patent where two or more persons made the invention independently: the applicant with the earliest date of filing, provided that application has been published (Article 60(2) EPC)7,9,14 | The US term, which ignores priority under 35 U.S.C. 119 (35 U.S.C. 154(a)(3))12 |
| The PCT time limits, which are computed from the priority date2 | Elements added in the later application: they are not covered by the earlier priority, and the later filing gives rise to its own right of priority for them (Paris Convention Article 4F)1 |
Priority rules in the US, Europe and China
United States
- A US application has the same effect as if filed on the date of the earlier foreign application, if it is filed within 12 months from the earliest date on which the foreign application was filed (35 U.S.C. 119(a))3.
- The 12-month period may be extended by an additional 2 months if the delay was unintentional, under regulations set by the Director (35 U.S.C. 119(a))3.
- A claim identifying the foreign application by number, office or country, and filing date must be filed with the USPTO (35 U.S.C. 119(b)(1))3.
- A nonprovisional application filed not later than 12 months after a provisional application has the provisional's date for an invention disclosed in the provisional in the manner required by 35 U.S.C. 112(a), other than best mode, if it contains a specific reference to the provisional. The 12 months may be extended by 2 months if the delay was unintentional (35 U.S.C. 119(e)(1))3.
- US law uses the effective filing date: the actual filing date, or the filing date of the earliest application to which the claimed invention is entitled to priority or benefit (35 U.S.C. 100(i))4.
Europe
- A person who has duly filed a patent, utility model or utility certificate application in or for a Paris Convention state or a WTO member enjoys a right of priority for a European application for the same invention for twelve months from the first filing (Article 87(1) EPC)5.
- Multiple priorities may be claimed, even from different countries, and time limits run from the earliest priority date (Article 88(2) EPC)6.
- The right of priority covers only those elements of the European application that are included in the application whose priority is claimed (Article 88(3) EPC)6.
- The priority date counts as the date of filing for the purposes of Articles 54(2), 54(3) and 60(2) EPC (Article 89 EPC)7.
China
- An applicant may claim priority from a first foreign filing within twelve months for an invention or utility model, or six months for a design (Patent Law, Article 29)10.
- Priority may also be claimed from a first filing in China, with the same twelve-month and six-month periods (Article 29)10.
- For an invention or utility model, the applicant makes a written declaration on filing and submits a copy of the first application within sixteen months from the first filing date (Article 30)10.
- Except for Articles 28 and 42 of the Patent Law, the filing date in the Patent Law means the priority date where priority is claimed (Implementing Regulations, Rule 12)11.
Priority date vs filing date vs effective filing date
| Date | What it is | Where it is used |
|---|---|---|
| Priority date | The filing date of the earliest application whose priority is claimed2 | Becomes the effective date for the purposes the filing date would otherwise serve, at the EPO8 |
| Filing date | The date an application is accorded on filing, for example under Article 80 EPC9 | May be an application's only effective date when no priority is claimed9 |
| Effective filing date (US) | Defined for each claimed invention: the actual filing date, or the earliest date to which it is entitled through priority or benefit4 | US law, 35 U.S.C. 100(i)4 |
Questions people ask
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Run Novelty SearchHow long do I have to claim priority?
Under the Paris Convention, twelve months from the first filing for patents and utility models, and six months for industrial designs and trademarks1. In the US, the 12-month period may be extended by 2 months if the delay was unintentional3. Other systems have their own restoration rules, for example PCT Rule 26bis.3 for an international application filed within two months after the priority period expires13; this page covers the US one.
Does the patent term run from the priority date?
No. Patents obtained with the benefit of priority have the same duration as they would have had without it1. In the US, priority under 35 U.S.C. 119 is not taken into account in determining the term12. In China, the rule that the filing date means the priority date does not apply to Article 42, the term provision11.
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