Ausplow (Pty) Ltd v Northpark Trading 3 (Pty) Ltd and Others

Ausplow (Pty) Ltd, the patentee of South African Patent ZA 95/0812 relating to improvements in seeding machinery, sued Northpark Trading 3 (Pty) Ltd for patent infringement. Northpark denied infringement and counterclaimed for revocation of the patent on grounds including lack of novelty and obviousness. Claim 1 of the patent was initially upheld by the Commissioner of Patents and found to be valid and infringed, but on appeal the Supreme Court of Appeal (in earlier proceedings) held claim 1 to be obvious and therefore invalid, issuing a provisional revocation order allowing Ausplow an opportunity to apply to amend the patent. Ausplow thereafter applied to amend claims 1 and 13 to cure the invalidity by narrowing their scope. The Commissioner of Patents (Murphy J) dismissed the amendment application on the basis that the amendments would not cure the obviousness. Ausplow appealed that refusal to the Supreme Court of Appeal.

The appeal was upheld with costs (including the costs of two counsel). The order of the Commissioner of Patents was set aside. The application to amend the specification of Patent ZA 95/0812 was granted, the provisional order of revocation lapsed, and the parties were ordered to pay their own costs in the amendment proceedings.

This case is significant in South African patent law for clarifying the principles governing post-revocation amendment of patent claims, particularly where invalidity is based on obviousness. It affirms the onus on the objector to prove continuing invalidity after amendment and emphasizes a constructive, purposive approach to claim interpretation. The judgment also confirms that courts should generally allow patentees an opportunity to amend patents to cure invalidity and provides authoritative guidance on the interaction between sections 51, 61, and 65 of the Patents Act.