NCR's acquisition of Alpharetta's Radiant Systems has drawn interest from law firms investigating whether shareholders could have gotten a better price if Radiant had shopped around.

At least four law firms have sent out feelers to shareholders. One, the Kendall Law Group in Dallas, Texas, said it is investigating whether Radiant, "breached their fiduciary duties by entering into the agreement without properly shopping for a deal that would provide better value for shareholders."

Other investigating firms are in Atlanta, Pennsylvania and New York. Each is questioning the process by which the deal was reached.

NCR, a Duluth technology company, announced Monday that it was acquiring Radiant Systems for $1.2 billion, or $28 a share. The company's stock had closed at $21.45 a share Monday.

Thursday, it closed at $28.52 a share.