No person shall be deemed an agent or attorney for this purpose unless he has indorsed the writ in the cause, or has appeared for his principal before the court, justice, referees or arbitrators, where the action is pending, or has given notice in writing that he is such attorney or agent.
N.H. Rev. Stat. Ann. § 517:6
Agency
Source
Official source: New Hampshire General Court. Reproduced from public-domain New Hampshire statutes; confirm against the official source for the current text. Not legal advice.