Davos 2014: Edward Snowden spying revelations seriously damaged our industry, admits Yahoo's Marissa Mayer

The chief executive of the internet search giant Yahoo, Marissa Mayer, admitted yesterday that the reputation of technology firms has been seriously damaged by last year's revelations that they provided digital data on customers to America's National Security Agency.

"We need to be able to rebuild trust with our users," she said at the World Economic Forum in Davos, Switzerland. "There are concerns with what the NSA is looking at and what it's being used for."

She said that internet firms ought to be permitted by the US authorities to reveal what requests for information they had received from security agencies. "Today we're prohibited from doing that," she said.

The 38-year-old, who became Yahoo CEO in July 2012, added that: "People don't know what information is being collected and how it's being used. And that's the transparency that we are asking for and trying to awaken a debate on."

Edward Snowden, a former NSA programmer, leaked details of the agency's surveillance operations last year, showing that it regularly and secretly extracted large amounts of data from internet and telecoms firms.

Earlier this month Ms Mayer fired her chief operating officer, Henrique De Castro, after he had served just 15 months in the job. Yahoo, which has been struggling to maintain advertising revenues, is due to publish its results for the fourth quarter of 2013 next week.

The chief executive of BT, Gavin Patterson, who was also on the Davos panel, echoed Ms Mayer's call for more transparency over state data collection, saying the rules on what information agencies can access from private firms such as BT needs to be overhauled. "The legislation has to catch up," he said. "It's often several steps behind. It's just too murky at the moment. There need to be clear regulations over what's acceptable and what isn't. It's not fit for purpose today. We've got to make sure it protects the rights of the individual, that it's not intrusive."

However, Mr Patterson added that there would always be some intrusion from the state because of the need to protect the public from the threat of terrorism. "I don't think it will ever be zero. People recognise that they have to give up some of their privacy to be protected," he said.

Also on the Davos panel was Cisco chief executive, John Chambers, who urged national governments to start working together to create transparent guidelines on privacy, safety and data collection.