A California federal judge approved a $16 million settlement between ADT Security Services and its customers who sued after claiming the company did not tell those who purchased its wireless security systems that they were not encrypted and, therefore, vulnerable to hacking.U.S. District Judge Jon S. Tigar of the Northern District of California gave the final stamp of approval to the class-action settlement on July 22 that was preliminarily approved in October 2017.Lawsuits were filed in Illinois, Arizona, California and …