When negotiations need to remain confidential, a letter of intent should obviously include a confidentiality cause. But in the case of startup companies–replete with their fresh and new ideas–a confidentiality clause is a requirement. Information will be exchanged during due diligence and the negotiations, thus the parties should agree on what information is confidential.
In most cases, the parties will expressly state that all information is confidential unless otherwise provided and that the obligation of confidentiality survives the term of the letter. Additionally, the parties should agree to the level of confidentiality that will be required regarding the terms of the letter of intent, the ongoing negotations, and any other information deemed confidential.