Which of the following is not a characteristic of void contracts?

• A. Defense of illegality cannot be waived
• B. Cannot be ratified
• C. Action for declaration of inexistence does not prescribe
• D. The inexistence can be assailed by third person

Answer: (D)

Void contracts have no legal effect from the start because their object or cause is illegal, impossible, or missing essential elements. Because there is nothing valid to ratify, such contracts cannot be cured by agreement after the fact, and the defense of illegality cannot be waived. The action to declare inexistence does not prescribe, since there is no valid obligation to enforce and the contract is deemed to have never existed.

The statement that the inexistence can be assailed by a third person isn’t a characteristic of void contracts. Typically, standing to seek a declaration of inexistence lies with the parties involved or with those whose rights are directly affected by the contract’s nonexistence; outsiders without a direct interest generally do not have the right to challenge it. Hence that option is the one that does not fit.