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 ODP’s consumer business, which includes the Office Depot and OfficeMax retail stores business. USR Parent, which is backed by Sycamore Partners, sent a letter to ODP’s board of directors proposing the acquisition, which is valued at $18.27 a share. ODP’s stock closed Thursday at $44.57 to represent a market capitalization of $2.39 billion. USR said recently it was evaluating a bid for ODP assets, after ODP reportedly rejected a buyout bid from USR for the entire company. “We believe our proposal represents a compelling opportunity for [ODP] and its shareholders,” USR wrote in its letter. “We look forward to working with the Company to negotiate and sign the necessary definitive agreements for the proposed transaction, and to proceed to closing the transaction as soon as practicable.” ODP shares have run up 52.1% year to date, while the S&P 500 has advanced 11.6%.

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