On 3 April 2017, the Full Court of the Federal Court of Australia handed down its decision in Coretell Pty Ltd v Australian Mud Company Pty Ltd  FCAFC 54. The decision, which was authored by Justice Burley (with whom Justices Nicholas and Jagot expressly concurred), considered, inter alia, the identification of the earliest date from which relief for infringement of an innovation patent may be awarded.
Australian Mud Company Pty Ltd (AMC) was the owner of two divisional innovation patents relating to a technique known as “core sample orientation”, used primarily in geological surveying and other drilling operations. In a decision of the Federal Court, Coretell Pty Ltd (Coretell) was found to have infringed the claims of each of the two patents and a cross-claim for invalidity was dismissed. Coretell appealed that decision to the Full Court on a number of grounds, several of which concerned the identification of the correct date in respect of which AMC could obtain relief for infringement of the patents.
In relation to this issue, the Full Court considered the earlier decision of Britax Childcare Pty Ltd v Infa-Secure Pty Ltd (No 3)  FCA 1019 (Britax) which had held that an innovation patent may be infringed from its effective filing date. (In the case of an innovation patent filed as a divisional from a standard patent application, the relevant date was the date of filing of the original patent application (even though the innovation patents did not then exist and were not open to public inspection)).
In Coretell, the Full Court overruled the Britax decision and found that the relevant date for determining infringement of an innovation patent (whether divisional or otherwise) under the Patents Act was not its effective filing date but, instead, the date of grant for the patent in suit. Accordingly, the Full Court held that the first date upon which AMC was entitled to relief was the date of grant of the two divisional innovation patents in issue.
The Full Court’s decision in Coretell is significant and will now largely prevent the situation where a patentee files a divisional innovation patent application upon a much older standard patent and then sues for acts of infringement that took place well before the invention was defined in any claims of the divisional application. Following Coretell, relief for infringement of an innovation patent will only date back to the date on which the innovation patent (divisional or otherwise) is granted.