Correct. Sealing a brief limits the viewing of the brief to the parties and the presiding judge. Obviously, a party to a lawsuit is entitled to see any argument submitted by the opposing party. If there is specific information in a given document that needs to be redacted for privilege or other such legitimate reason, then that can be done on a case by case basis. But any relevant information must be presented to the court and the opposing party in order to allow all parties to defend themselves.