Verifone Systems Inc. shares skyrocketed late Monday after the payment and business services provider and private-equity firm Francisco Partners said they have struck a deal under which an investor group led by Francisco Partners will acquire Verifone for $23.04 a share in cash, or about $3.4 billion including Verifone's debt and a premium of about 54% on Monday's closing price of $15. Verifone's board of directors unanimously approved the agreement and recommends stockholders vote in favor of the transaction, the companies said in a statement.