An authority expressed in general terms, however broad, does not authorize an agent to act in his own name, unless it is the usual course of business to do so.
S.D. Codified Laws § 59-3-9
Exceptions to general authority--Agent cannot act in own name
Source: CivC 1877, § 1361, subdiv 1; CL 1887, § 3984, subdiv 1; RCivC 1903, § 1680, subdiv 1; RC 1919, § 1262 (1); SDC 1939, § 3.0205 (1).
Official source: South Dakota Legislature. Reproduced from public-domain South Dakota statutes; confirm against the official source for the current text. Not legal advice.