Blackstone announced Tuesday it will acquire sandwich chain Jersey Mike's Subs. The asset management firm said the majority ownership stake will be purchased by its "most recent flagship private equity vehicle" and other funds it manages.Blackstone aims to complete the purchase early next year. Reuters reported that the deal values the company at around $8 billion, including debt.SUBWAY AGREES TO SALE TO ROARK CAPITAL, ENDING NEARLY 6 DECADES OF FAMILY OWNERSHIP Blackstone said in a press release that the p ...