Penn Shipping appears as an operator by 1958–59, later also an owner, and remains recorded in 1980–81. It operated Penn Tanker; vessels generally had Penn-prefixed names until the later 1970s.
Webb & Knapp is recorded in connection with hull insurance, leading Rosanoski to suggest that shipping may have been an offshoot of its other interests. The real-estate firm was controlled from 1949 by William Zeckendorf, who went bankrupt in 1965. The precise relationship is not established.
USA, New York.
Keep the explicit scope label independent; no alias or company identity is inferred.