Payment processing service Applied Merchant Systems has merged with BlueSquare Resolutions, an Arizona company operating in the same space. Applied Merchant Chief Executive Jonathan Severn said the deal had been in the works and was driven by how his Calabasas-based company and BlueSquare, in Scottsdale, complement each other. “It’s our intent to acquire and partner with companies with industry-leading managers,” Severn said in a prepared statement. “(Chief Executive) Sabin Burrell and BlueSquare are tremendous additions to the family.” Terms of the deal between the two privately held companies were not disclosed. Burrell becomes a shareholder and senior executive of Applied Merchant while remaining head of BlueSquare. Applied Merchant handles more than $4 billion in annual processing volume of debit and credit card purchases in retail stores, over the internet and through mobile devices.