Under the pre-raising the bar legislation Syngenta opposed Bayer’s application for the synergistic combination of known active substances which individually have different but known insecticidal properties. The aim of Bayer’s alleged invention is to provide an insecticidal composition of the nicotinergic acetylcholine receptor modulators and anthranilamides with a better activity spectrum than the compounds have individually. This synergistic effect is satisfied when the action of the active compound combinations exceeds the total of the actions of the active compounds when applied individually. The specification states that the weight ratio’s of the active ingredients can be varied across a relatively wide range but notes that the synergistic effect is particularly pronounced in certain weight ratios. Claim 1 claims an insecticidal composition comprising a synergistically effective active compound combination of one compound of formula (I) selected from the group consisting of Ia, Ie, Ig, Ik, Im and one compound of formula (II-1) in a weight ratio of 25:1 to 1:10.
Prior art publication D4 is directed to various anthranilamides, their N-oxides and their use for controlling invertebrate pests. Among the compositions disclosed in D4 are the anthranilamides of formula (II-1) mixed with at least one additional biologically active compound or agent including insecticides, fungicides, nematocides and bactericides. D4 further specifies compounds Ia, Ik, Im as preferred insecticides.
It was well known to persons skilled in the art (PSA) at a general level that combinations of active compounds could have synergistic effects such as providing improved insecticidal activity, broadening the spectrum of activity and minimising the development of resistance. However, Bayer argued that for particular combinations synergy was certainly not a given or inevitable and that there was no reasonable expectation on the part of the PSA that synergy would occur.
The Judge found that the PSA could be reasonably expected to ascertain, understand and regard D4 as relevant. Further, given that D4 specifies compounds Ia, Ik, Im as preferred insecticides, the PSA would try them when formulating a combination insecticide. The Judge then went on to conclude that all but two of the applications claims lacked an inventive step as the PSA would discover the synergy and weight ratios between the compounds through routine steps of optimisation.