MDU RESOURCES GROUP, INC. FORM 10-K FOR PERIOD ENDED 12/31/2009

Company

MDU RESOURCES GROUP INC

Filed

February 17, 2010

Period of Report

December 31, 2009

Accession Number

0000067716-10-000030

A 10-K is a company's comprehensive annual report, required by the SEC. It includes audited financial statements, a description of the business, risk factors, and management's discussion of results. Learn more about 10-K filings →