It is not always reasonable to pursue all reasonable points

In today’s costs judgment in MMI Research Ltd v Cellxion Ltd & Ors [2012] EWCA Civ 139 the Court of Appeal, applying the general rules on costs, declined to award costs to the defendants, which had ultimately prevailed on a question of obviousness, because they had raised so many issues on which they lost. Notwithstanding that the points raised may have been individually reasonable, the sheer number was not:

Always reasonable
We think the defendants were indeed profligate in the number of points they took. A defendant cannot take as many "reasonable" points as it likes and not have to pay for any of them if they are unsuccessful. If he has a large number of potential such points he should make a judgment as to which are the better ones. A good test to apply is not merely "is this point a reasonable runner?" but also "which of my reasonable runners are the best few?" If only a few such points are run and all but one fails, the court may deprive the party of its costs of the unsuccessful points. But there comes a point when more sanction is called for. This is particularly important in a patent action where very often a host of possible defences could be run. A reasonably strict costs regime should make a defendant concentrate on his best – which may indeed also give him a better chance of winning.

The Court not only refused to grant costs in respect of the unsuccessful defences, but also in respect of the point on which the defendants had prevailed: “That we think is the appropriate price to be paid for its profligacy.” However, the Court did not go so far as to award costs against the defendants, as the patentee had asked.