ISC cites query about ?unusual? activity of common stock

ISC cites query about ôunusualö activity of common stock    International Shipholding Corp., a New Orleans-based provider of transportation services, said Wednesday it had been contacted by a representative of the New York Stock Exchange who asked for an explanation of 'unusual market activity' in ISC's common stock.
   'The exchange requested that the company issue a public statement indicating whether there are any corporate developments that may explain the unusual activity,' ISC said in a statement.
   'In response to the inquiry, the company has advised the exchange that its policy is not to comment on unusual market activity or rumors,' ISC said. Company officials did not return calls to Shippers' News Wire.