Dividing And Conquering: Best Method Obligations Follow Every Divisional Patent Application

In an important decision, the Full Federal Court in The NOCO Company v Brown and Watson International ¹ held that the relevant date for assessing the best method known to the applicants is the filing date of each divisional application. This judgment carries significant implications for patent filing and litigation strategies, as patentees must consider the adequacy of the best method disclosures in existing and future divisional patent specifications.

Background

As we previously reported here, this case involved NOCO's three patents from the same family for portable vehicle jump starters, which the patentee alleged that Brown and Watson International Pty Ltd (B&W) had infringed.

Each divisional patent claimed a priority date from 2014 based on the PCT application, despite being filed between 2020 and 2022, which is standard practice. In response, B&W cross-claimed for invalidity, including on best method grounds.