Michael and Matthew Leible, father and son who together span some 50 years in the out-of-home advertising business, have formed Generation Outdoor, an independent outdoor ad company in New York. Michael Leible, CEO of the agency, began his 40-year career at Daniel & Charles Advertising before moving to Diversified Media in Washington, D.C. He has held several other posts and was most recently president of Medallion Taxi Media, a division of Medallion Financial Corp. that sold taxi-top advertising. Matthew Leible will serve as president of Generation Outdoor. Prior to the new venture, he was outdoor media director at Horizon Media in New York.