James Abrahams QC and Henry Ward represented the Appellant, Napp, in this appeal concerning Napp’s patent for a transdermal patch for delivery of the analgesic drug buprenorphine.
At first instance the judge had held that the patches produced by the Defendants, Dr Reddy’s and Sandoz, did not infringe Napp’s patent because they used patches with a different formulation to that described in Claim 1 of the patent.
Napp appealed on the basis that:
- The judge had erred in finding that the quantities specified in Claim 1 referred to those found in the final product rather than ‘input’ quantities in formulating the patch itself.
- The judge had applied too narrow a construction to Claim 1 in holding that stated quantities were specified to the nearest whole number.
The Court of Appeal upheld the judge’s approach to construction and dismissed the appeal. In relation to numerical ranges, Floyd LJ held that in construing the level of specificity to apply, the use of the words ‘about’ might indeed imply a greater degree of imprecision than the normal rounding convention, but in the instant case this did not extend to more than 1% either side of the stated 10%.