The companies asking the government to muzzle National Security Agency's programs are: Mountain View's Google and LinkedIn, Cupertino's Apple, Menlo Park's Facebook, Sunnyvale's Yahoo and San Francisco's Twitter.
The companies are publishing open letters in several United States newspapers on Monday.
Documents leaked by NSA contractor Edward Snowden revealed the government collected information from millions of people without their knowledge.
The NSA says everything it is doing is perfectly legal.
