Merck & Co. Inc. v Sankyo Company Limited

Merck & Co. Inc. lodged a patent application for derivatives of C-076 compounds, which were later accepted with modifications. Sankyo Company Limited opposed the grant of a patent on the application. The opposition was based on the grounds of anticipation and non-compliance with the provisions of section 40 of the Patents Act 1952. The hearing took place in Sydney on 11 and 12 March 1991. The court had to decide the priority dates of the claims of the accepted Merck application. The court found that the accepted claims which refer to the substituent at the 25-position as iso-propyl claim matter in substance disclosed in the specification as a result of the amendment from n-propyl which was the original definition of the 25-substituent. The court concluded that the claims to compounds per se defined in terms of the formula are directed to different subject matter in the original and accepted applications. The court found that claims to compounds defined in terms of a structural formula in which the 25-substituent is iso-propyl involve new matter and should be accorded a later priority date in accordance with s.159A. The earliest possible priority date for claims to compounds defined in terms of an iso-propyl substituent is therefore 18 December 1981. The opposition succeeds on the ground of anticipation. The applicant is allowed 60 days from the date of this decision to propose amendments with a view to removing the anticipated subject matter. Costs are awarded in favour of the opponent.