The High Court overturned a decision in October, 2000, by the Full Federal Court of Australia, declaring the patent invalid due to obviousness. The latest judgment restores the patent’s validity and agrees with AstraZeneca’s argument that the patent is not obvious and involves inventive step.

The proceedings will now return to the lower courts for disposal of remaining issues.

Australia represented about 2 per cent of Losec worldwide sales in 2001.