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7.12.4 Calculating the Length of the Extension of Term

Date Published

Key Legislation:

Patents Act:

  • s33 Applications by opponents etc.  
  • s36 Other applications by eligible persons  
  • s65 Date of patent  
  • s70 Applications for extension of patent  
  • s71 Form and timing of an application  
  • s77 Calculation of term of extension  

Patents Regulations:

  • 6.3 Date of patent

The maximum length of an extension of term is 5 years. Under sec 77, the length of an extension is equal to the period between the date of the patent (sec 65) and the date of the earliest first regulatory approval, reduced (but not below zero) by 5 years. Thus:

  • where the period between those two dates is 5 years or less, a patent will not be eligible for an extension of term;
  • a period of 10 or more years will allow a full 5 year extension; and
  • a period of in between 5 to 10 years will have an incremental extension of term somewhere between 0 and 5 years.

A simple way to calculate the date to which a patent can be extended is as follows:

Time Between the Date of the Patent and the Date of First Regulatory Approval (Years)Extension Granted
Less than 5 yearsNo extension
Between 5 and 10 years15 years from the date of first regulatory approval
10 years or more25 years from the date of the patent

The date of a patent is usually the date of filing of the relevant complete specification. However, reg 6.3 provides for the determination of a different date in a number of circumstances. The most common of these is where there is a patent granted on a divisional application, in which case the date of the patent is the date of filing of the complete specification in which the invention was first disclosed. The other circumstances relate to applications made under sec 33 to sec 36 or applications in relation to which the time for making the application has been extended.

Examples of Calculations

  • The date of the patent was 14 August 1986 and therefore without an extension of term, the patent would expire on 14 August 2006. The first regulatory approval was given on 12 June 1990. The difference between the date of the patent and regulatory approval is less than 5 years and consequently there is no extension of term.

    Subsequent regulatory approval of goods containing other substances disclosed and claimed int he patent will not change this outcome; the calculation is based on the earliest first regulatory approval date.

  • The date of the patent was 28 November 1989, which was the date of filing of the complete specification. Without an extension of term, the patent would expire 20 years from that date on 28 November 2009.

    The first regulatory approval was given on 4 April 1996. The difference between the date of the patent and the marketing approval is more than 5 years but less than 10.

    The patent, if it met the requirements of sec 70 and sec 71, would be eligible to be extended until 15 years from the date of approval, i.e. an extension until 4 April 2011.

  • The date of the patent was 20 June 1980 and therefore without an extension of term the patent would expire on 20 June 2000.

    The first regulatory approval was given on 18 November 1991. The difference between the date of the patent and regulatory approval is more than 10 years. Consequently, the patent is entitled to a full extension of 25 years from the date of the patent, i.e. an extension until 20 June 2005.

 

Amended Reasons

Amended Reason Date Amended

Reinstating content relating to decisions in Commissioner v Ono and Merk v Sandoz inadvertently omitted during manual migration.
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