A letter from eight prominent online companies to President Obama and Congress calls for reform of government surveillance programs, outlining concerns about the way the National Security Agency monitors online and telephone communications.

The companies - AOL, Apple, Facebook, Google, LinkedIn, Microsoft, Twitter and Yahoo - sent the letter this week, urging the federal government to institute reforms that ensure government surveillance efforts are clearly restricted by law, proportionate to the risks, transparent and subject to independent oversight.

"The tech giants' message couldn't be any clearer or more welcome - the government's massive spying authorities must be reined in immediately," says Michelle Richardson, legislative counsel at the American Civil Liberties Union's Washington legislative office. "Widespread support for reform will only continue to grow until Congress and the administration deal with out-of-control spying head on by prohibiting indiscriminate surveillance."

Fueling concerns about NSA activities are what seem to be never-ending leaks from former NSA contractor Edward Snowden. Among the latest was a Dec. 4 Washington Post report that the agency is gathering nearly 5 billion records a day on the whereabouts of cellphones around the world, which allows it to track the movements of individuals - and map their relationships - in ways that would have been previously unimaginable.

Shaken Trust

Revelations about NSA surveillance activities have shaken the trust of Yahoo customers, CEO Marissa Mayer says. "It is time for the United States government to act to restore the confidence of citizens around the world," she says.

Mayer and her colleagues at the seven other companies have a legitimate gripe primarily because of the impact on their reputations and profitability, says Jacob Olcott, cybersecurity principal at the security advisory firm Good Harbor Consulting. "The U.S. government needs to recognize and account for the deep harm that it is likely inflicting on American businesses because of these surveillance efforts," Olcott says. "Today, that conversation appears one-sided."

Allan Friedman, a Brookings Institution fellow who focuses on cybersecurity's impact on the economy, says the technology companies raise a series of important concerns about NSA practices, ranging from the long-established processes of requesting specific records to the newer ones involving wholesale data collection.

Because the NSA collects so much data from American firms, "the foreign press and even sophisticated policymakers have combined or conflated many of these concerns and come to the conclusion that American firms can't be trusted," says Friedman, co-author of the forthcoming book Cybersecurity and Cyberwar: What Everyone Needs to Know to be published by Oxford University Press early next year.

"In in the short-run, the adverse publicity will have at least some small effect on their bottom line," he says. "If they can't win back the trust of foreign consumers and governments, then the long-run outcome might be policies that promote national or regional businesses to take their place."

Google CEO Larry Page, in a statement accompanying the letter announcing the launch of a website - Reform Government Surveillance - to promote the companies' cause, says NSA efforts have thwarted steps companies like Google have taken to protect privacy, such as investing in encryption. "This is undermined by the apparent wholesale collection of data, in secret and without independent oversight, by many governments around the world," Page says. "It's time for reform, and we urge the U.S. government to lead the way."

Five Principles