 Shares of ODP Corp. rallied 5.1 in premarket trading Friday, after the office supplies retailer received an unsolicited 1.0 billion bid from Staples parent USR Parent Inc. to buy ODPs consumer business, which includes the Office Depot and OfficeMax retail stores business. USR Parent, which is backed by Sycamore Partners, sent a letter to ODPs board of directors proposing the acquisition, which is valued at 18.27 a share. 