No one can sue in the name of another.

Explanation

(English-origin maxim.) A man must bring suit in his own name — no one may litigate on behalf of another without proper legal authority such as power of attorney or guardianship.

Where this applies

• A woman tries to file a lawsuit on behalf of her adult brother without any power of attorney, and the court dismisses it because she cannot sue in someone else's name.
• A neighbor attempts to bring a nuisance claim using another resident's name, and the court throws it out because each person must sue on his own behalf.
• A business associate files a fraud complaint in the name of a company he does not represent, and the case is dismissed because he has no authority to sue for that entity.