Nor anyone acting on its behalf
See also delegation.
That fabulous Latin construction nemo dat quod non habet ought, but does not, nix that tedious drafting construction: “neither X, nor anyone acting on its behalf, may do Y”.
For if, by the lights of the law, a principal has no right to do a thing, it follows as a matter of ineffable Latin logic that neither may her ox, ass, servant, agent, attorney, nominee, delegate or other mortal representative do that thing, unless such a representative independently happens to be entitled to do that thing. If so the representative will not be acting under the contract at hand, nor really on the principal's behalf, so this purported contractual structure will fall upon stony ground.
So, be bold, young attorney: banish it from your lexical armoury.
Plain English Anatomy™ Noun | Verb | Adjective | Adverb | Preposition | Conjunction | Latin | Germany | Flannel | Legal triplicate | Nominalisation | Murder your darlings