Apple says it's challenging government efforts to overcome encryption on at least 14 devices nationwide in addition to the phone of a San Bernardino, California, shooter.
Lawyers told a New York federal magistrate judge that Apple is opposing relinquishing information on at least 15 devices in court cases in California, Illinois, Massachusetts and New York.
A Feb. 17 Apple court document was unsealed Tuesday. In a court filing, the government says Apple's position has been inconsistent.
Apple attorney Marc Zwillinger said the government has asked it to perform "burdensome and involved engineering" to circumvent security.
The company's highest-profile fight has been over information on the phone of a San Bernardino attacker.
Apple first challenged the government in October in an otherwise routine drug prosecution in New York.
Apple has resisted providing a piece of programming that would help the FBI access the phone. Apple argues that governments, both in the U.S. and overseas, are likely to use the program in other cases, undermining data privacy.
- Apple CEO Tim Cook says U.S. government should withdraw demand for iPhone hack help
- San Bernardino victims to oppose Apple on iPhone encryption
In an interview Tuesday with the Financial Times, Microsoft founder Gates says "this is a specific case where the government is asking for access to information." He likened it to the police getting records from a phone company.
The heads of many tech companies like Facebook, Twitter and Google have sided with Apple.
Bill Gates's view
Bill Gates told the Financial Times Tuesday that the firm should help the U.S. government to hack into a locked iPhone as part of an investigation into the San Bernardino shooting.
However, later in an interview with Bloomberg TV, Gates said seeing headlines saying that he backed the FBI "was disappointing because it doesn't state my view on this."
He went on to say there are situations, such as cases where terrorism could be stopped, where the government should get access to users' information, provided the right safeguards are in place.
"I do believe there are sets of safeguards where the government shouldn't have to be completely blind," he added.
Facebook CEO Mark Zuckerberg on Monday expressed his support for Apple while in Barcelona, Spain, to speak at the Mobile World Congress, saying he believes in helping the government in its fight against terrorism but that encryption is important.
"I don't think that back doors into encryption is going to increase security or is in the direction the world is going," he said.
Apple's supporters planned to protest the FBI's demands on Tuesday evening outside Apple's stores in about 50 cities in the U.S., the U.K., Germany and Hong Kong.
A Pew Research Center survey found that 51 percent of Americans said Apple should unlock the iPhone, while 38 percent said Apple should not — and that it should ensure the security of user information. The remainder gave no opinion. The telephone survey was conducted Feb. 18 through Feb. 21 among 1,002 adults.