If the person who was able to gain knowledge of the invention was under an obligation to maintain secrecy, the invention cannot be said to have been made available to the public, provided the person did not breach that obligation.
In T 1081/01 the board held that information provided subject to a confidentiality agreement did not become available to the public merely by reason of the expiry of the obligation to keep it confidential. Some separate act of making it available to the public would be needed. This conclusion was in agreement with the conclusion reached in T 842/91, where permission to publish a text was considered merely as permission to make the text available to the public, and not as actually making the text available to the public. If the obligation to maintain secrecy stems from an express agreement that has been observed, the information has not been made available to the public. Less clear cut are cases of tacit secrecy agreements. Whether a tacit secrecy agreement between parties exists, depends on the peculiar circumstances of the specific case (T 972/02, T 1511/06).
In T 1309/07 the board ruled that it was clear from the file that 17 520 combustion-engine pistons of a certain type had been supplied to Renault before the priority date. The question was whether, at the time of delivery, a tacit secrecy agreement had applied. In view of the large quantity involved, and the fact that pistons of this type were offered in a pre-published spare-parts catalogue, the board took the view that they had been supplied not for test purposes but for normal series production, so from that point onwards no such agreement could have existed.