How do ‘intermediate range’ cases affect unexpected results arguments in patents?

‘Intermediate range’ cases present unique challenges when arguing for unexpected results in patent applications. MPEP 716.02(d) provides guidance on this issue:

The court has held that unexpected results for a claimed range as compared with the range disclosed in the prior art had been shown by a demonstration of ‘a marked improvement, over the results achieved under other ratios, as to be classified as a difference in kind, rather than one of degree.’

In these cases:

  • The claimed range falls within a broader range disclosed in the prior art
  • Applicants must show that the specific claimed range produces unexpected results
  • The results must be significantly better than those at the endpoints of the prior art range

Demonstrating unexpected results in intermediate range cases often requires extensive data and careful argumentation to overcome prima facie obviousness.

To learn more:

Tags: patent applications, prior art, unexpected results