Rules of Professional Conduct
7. Information About Legal Services
ER 7.5. Firm Names and Letterheads
(a) A lawyer shall not use a firm name, letterhead or other professional designation that violates ER 7.1. A trade name may be used by a lawyer in private practice if it does not imply a connection with a government agency or with a public or charitable legal services organization and is not otherwise in violation of Rule 7.1.
(b) A law firm with offices in more than one jurisdiction may use the same name or other professional designation in each jurisdiction, but identification of the lawyers in an office of the firm shall indicate the jurisdictional limitations on those not licensed to practice in the jurisdiction where the office is located.
(c) The name of a lawyer holding a public office shall not be used in the name of a law firm, or in communications on its behalf, during any substantial period in which the lawyer is not actively and regularly practicing with the firm.
(d) Lawyers may state or imply that they practice in a partnership or other organization only when that is the fact.
COMMENT TO 2003 AND 2012 AMENDMENTS
 [2012 Amendment] A firm may be designated by the names of all or some of its members, by the names of deceased or retired members where there has been a continuing succession in the firm's identity, or by a trade name such as the “ABC Legal Clinic.” A lawyer or law firm may also be designated by a distinctive website address or comparable professional designation that complies with ER 7.1.
 [2003 Amendment] With regard to paragraph (d), lawyers sharing office facilities, but who are not in fact associated with each other in a law firm, may not denominate themselves as, for example, “Smith and Jones,” for that title suggests that they are practicing law together in a firm.
 [2003 Amendment] “Of counsel” designation may be used to state or imply a relationship between lawyers only if the relationship is close, personal, continuous, and regular.