Transactions and Communications with Persons Other Than Clients
Truthfulness
Rule 4.1 forbids false statements of material fact or law to a third person and forbids failing to disclose a material fact when disclosure is necessary to avoid assisting a client's criminal or fraudulent act (unless Rule 1.6 forbids it). There is no duty to help the adversary: negotiating positions and puffery are permissible, but misstating facts, law, or the lawyer's authority to settle is not.
Represented persons
Rule 4.2 bars communicating about the subject of the representation with a person the lawyer knows to be represented, unless the other lawyer consents or the law or a court order authorizes it - service of process and legally authorized investigations are examples. The rule covers persons the lawyer reasonably should know are represented. In organizations, contact with employees is restricted when the employee's acts may bind the entity or the employee's statements may be admissions, or when the employee may possess privileged information.
Unrepresented persons
Rule 4.3 requires the lawyer to correct any misunderstanding that the lawyer is disinterested, to avoid giving legal advice other than to obtain counsel, and to make clear the lawyer's role. Negotiating and drafting documents for an unrepresented person remains permissible, but fairness demands clarity about whose interests the lawyer serves.
Third persons generally
Rule 4.4 prohibits means having no substantial purpose other than to embarrass, delay, or burden a third person, and prohibits obtaining evidence by violating a legal privilege. If a lawyer receives a document she knows was inadvertently sent, she must promptly notify the sender.
Traps
Accepting a represented party's own "consent" to talk; assuming every corporate employee is off limits; failing to send the inadvertent-disclosure notice; believing that a truthful statement can never violate 4.1.
Worked example
An opposing party who is represented telephones the lawyer to discuss the case. The lawyer must decline to discuss the matter and should tell the party to contact her own lawyer.