US mobile operator Verizon has been fined $1.35m (£950,000) by the Federal Communications Commission (FCC) for the use of supercookies which tracked phone customers internet browsing history and habits without their permission.

The supercookies were first used by Verizon in December 2012, but the programs existence wasnt disclosed by the company until October 2014, when they became subject to heavy criticism from consumers and industry figures alike. In March 2015, Verizon updated its privacy policy to reveal the use of the trackers, and gave people an option to opt out.

The supercookies were given the name due to the difficulty users faced in detecting and blocking them, and were used by Verizon to deliver targeted ads to its mobile customers. The company is currently in the midst of expanding its advertising and digital business, fueled by its purchase of AOL in May 2015, and has shown an interest in acquiring the embattled Yahoo.

“Consumers care about privacy and should have a say in how their personal information is used, especially when it comes to who knows what theyre doing online,” said Travis LeBlanc, chief of the FCCs Enforcement Bureau. “Privacy and innovation are not incompatible. Companies can offer meaningful transparency and consumer choice while at the same time continuing to innovate.”

“Verizon gives customers choices about how we use their data, and we work hard to provide customers with clear, complete information to help them make decisions about our services,” said a Verizon spokesperson. “Over the past year, we have made several changes to our advertising programs that have provided consumers with even more options. Todays settlement with the FCC recognises that.”