Priority Dates - what are they?

When an application is filed it is given a filing date, also known as a priority date. This priority date is important as it is often the date from which most deadlines are calculated, though is also important when several competitors are filing applications for similar inventions or for improvements in a similar field.

In the case of several independent parties filing an application for the same invention on different dates, most countries adopt a ‘first-to-file’ approach where the first filed application has priority. The second application may proceed for subject matter which is not contained in the first application, providing it is patentable. The United States is the notable exception, where a difficult to prove ‘first-to-invent’ system is adopted. Applicants considering the US for patents should keep accurate, dated, log books showing their developments and progress.

Of the deadlines calculated from the priority date, the most important is the deadline for filing overseas ‘convention’ applications. These are applications which, while filed overseas, claim the original filing date of the first application – a significant advantage to IP owners who can delay filing overseas but still receive the earliest possible filing date. For patents this convention period is 12 months, with a shorter 6 month period for designs and trade marks.

The general rule is to obtain as early a priority date as practicable for applications to protect your IP. This is however tempered with your ability to meet subsequent filing deadlines, and development of your technology to the point that useful IP protection can be obtained.