In a recent decision, the EPO’s Boards of Appeal have confirmed the importance of filing data to support arguments relating to sufficiency of disclosure in EPO opposition proceedings. The patent concerned related to a mixture of fish oil and fruit juice which was alleged to have anticancer properties. The opponent argued the constituents required to achieve the anticancer effect were not sufficiently disclosed, but failed to provide enough data to convince the Board of Appeal. Hence, the Board was satisfied the claimed composition was sufficiently disclosed and ordered that the patent be maintained in amended form.