Yes. The European Commission treats all proposals received as confidential, as well as any related information, data and documents received from each applicant. The whole process of handling and evaluating proposals is carried out in compliance with strict confidentiality rules, and proposals are archived under secure conditions at all times.
Similarly, external experts involved in the review of project proposals are also bound by confidentiality obligations. Evaluators, observers and other experts have to sign a contract with the European Commission, including a code of conduct which sets forth very strict confidentiality obligations.