Callander said the people affected were contacted by Power Marketing, a former sales contractor of Slingshot that cold-called potential customers.
"We have accepted the findings of the Commerce Commission and have apologised to the 27 customers who were impacted by the actions of the third party telemarketing company, Power Marketing," Callander said.
"We accept that we got some things wrong and have since addressed those areas of concern, including the termination of the contract with Power Marketing. The customer complaints occurred between 2009-2011," he said. "We have co-operated fully with the Commerce Commission since the charges were laid ..."
The Herald requested comment from Power Marketing managing director Paul Ross via email yesterday evening but he did not respond by time of publication.
In early 2011, former Power Marketing staff claimed to the Herald on Sunday that they had signed up people for internet packages even though they did not have computers.
Letter writers to the paper claimed their elderly parents were signed up for Slingshot accounts without being aware of what they were doing.
At the time, former Power Marketing staff also claimed the telemarketing company's employees had accessed a Telecom customer sales database known as Wireline.
This database contained an estimated 2.15 million names, as well as addresses and billing details.
Slingshot presently holds about 10 per cent of the broadband market and is the third largest player in this space after Telecom and Vodafone.