BERLIN — European privacy activists have filed complaints against Apple over its use of software to track the behavior of iPhone users.

The Vienna-based group NOYB – short for "none of your business" – said Monday that it has asked data protection authorities in Germany and Spain to examine the legality of Apple's tracking codes.

The codes, known as IDFA or Identifier for Advertisers, are similar to the cookies that websites use to store information on user behavior.

NOYB says the iOS operating system creates unique codes for each iPhone that allow Apple and other third parties to "identify users across applications and even connect online and mobile behaviour."

The group argues that this amounts to tracking without users' knowledge or consent, a practice that is banned under the European Union's electronic privacy rules.

"Tracking is only allowed if users explicitly consent to it," said Stefano Rossetti, a lawyer for NOYB. The privacy group said it is currently reviewing a similar system used by Google.

Apple dismissed the claims in NOYB's complaint, saying they were "factually inaccurate and we look forward to making that clear to privacy regulators should they examine the complaint."

"Apple does not access or use the IDFA on a user's device for any purpose," the company said.

"Our aim is always to protect the privacy of our users," Apple said, adding that the latest version of its software gives users greater control over whether apps can track them, including whether their information can be linked with data from third parties "for the purpose of advertising, or sharing their information with data brokers."

"Our practices comply with European law," it said.

NOYB, founded by privacy activist and lawyer Max Schrems, has filed numerous cases against major tech companies including one against Facebook that recently led the European Union's top court to strike down an agreement that allows companies to transfer data to the United States over snooping concerns.