NSA Internet Phone
The U.S. National Security Agency logo appears on an Apple iPhone display. Reuters

The U.S. National Security Agency's (NSA) operation to collect data directly from phone companies doesn't apply directly to T- Mobile USA or Verizon Wireless because of those firm's ownership or partial ownership by foreign companies, according to a report.

Germanys' Deutsche Telecom AG (ETR:DTE) owns 74 percent of T-Mobile, while the U.K.'s Vodafone (LON:VOD) owns 45 percent of Verizon Wireless.

The Wall Street Journal, citing sources familiar with the matter, said that the NSA still believes it can capture about 99 percent of all phone traffic because most calls at some point travel over U.S.-company-owned networks.

The report concluded that while the amount of data excluded is small, the policy of excluding firms with foreign ties could become more difficult for the U.S. as investors, including foreign ones, continue to play a large role in building and operating the communications networks.