BRIEFLY / ADVERTISING : True North to Buy Stake in Black Agency

True North Communications Inc., the world’s seventh-largest advertising company, agreed to buy a 49% stake in closely held Don Coleman Advertising for an undisclosed sum to extend its reach to African Americans. Don Coleman would join Chicago-based True North’s multicultural agencies, forming the largest such agency network in the U.S. and giving it $200 million in aggregate billings. Don Coleman, based in Detroit, is the third-biggest African American-owned ad firm. The move will boost True North’s ability to focus on multicultural customers as African American, Latino and Asian populations grow at seven times the rate of the general U.S. market, True North said. Shares of True North closed down 6 cents at $32.88 on the NYSE.