BlackRock raised its stake in Saks to 12.7 percent, bolstering the investment fund's profile among financial and retail heavyweights with a big bet on the luxury chain. The giant money-management firm said it bought 20.3 million shares in the owner of Saks Fifth Avenue "in the ordinary course of business." BlackRock has no intention of "changing or influencing the control" of Saks, according to a filing made yesterday with the Securities and Exchange Commission. BlackRock's filing follows a noisy year for Saks investors. Last spring, Saks management fended off a proxy challenge from longtime shareholder Peter Schoenfeld, who charged that executives damaged the company's brand when they discounted designer goods by 70 percent after the Wall Street crisis hit its well-heeled shoppers in September 2008.