A woman displays "Siri", voice-activated assistant technology, on an Apple iPhone 4S in Taipei on July 30, 2012. (MANDY CHENG/AFP/GETTY IMAGES)

Apple keeps voice queries from Siri for up to two years, the company told Wired on Friday morning.

The company, which introduced the voice assistant software in the iPhone 4S in 2011, had never shared the full specifics of how it stores data. But after a Wired article Thursday that included concerns from the American Civil Liberties Union, the company revealed more information about how it collects and stores users’ voice queries.

Whenever users speak into the voice assistant software, Apple told Wired, the clip is sent to Apple’s data servers for analysis. Clips are associated with a random identification number, but not with users’ Apple ID accounts or e-mails. After six months, the report said, Apple “disassociates” voice clips from the original identification numbers.

Apple may keep that anonymized data for up to two years, the company said.

As Apple has disclosed on its privacy statement for Siri, Apple will delete Siri user data if users turn off the feature.

The disclosure did not fully meet with the satisfaction of ACLU lawyer Nicole Ozer, whose concerns prompted the Thursday article.

In a statement to Wired, Ozer said that she would like Apple to post this information on the frequently asked questions page for Siri, to let potential customers know how long the company may store their voice clips.

Apple did not immediately respond to a request for comment.

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