A federal grand jury has issued a subpoena to Pandora Media for an investigation that the company believes is related to information-sharing processes on the Apple and Android mobile platforms. Pandora revealed this information Monday in a filing related to its initial public offering.

In the documents, the Oakland, Calif.-based music-streaming company said it believes that several other companies across the industry also received subpoenas. Pandora was informed that it is not the specific target of the grand jury investigation.

When asked about the investigation, Pandora spokeswoman Deborah Roth declined to comment further. “Our registration statement contains the totality of public information about Pandora at this time,” she said.

The contents of the Pandora IPO were reported earlier by the Wall Street Journal. The company was among those highlighted in an earlier Journal investigation that found several apps were transmitting personal information to other companies without users’ consent.

In earlier IPO documents, Pandora said it expects it will have to join a self-regulating body or to comply with new privacy regulations, a potentially costly factor.

 "Government regulators have proposed 'do not track' mechanisms, and requirements that users affirmatively 'opt-in' to certain types of data collection that, if enacted into law or adopted by self-regulatory bodies or as part of industry standards, could significantly hinder our ability to collect and use data relating to listeners," the filing said.

Several politicians have announced privacy bills at the state and federal levels. U.S. Rep. Jackie Speier (D-Calif.) introduced her “Do Not Track Me Online Act of 2011” in February. On Monday, California State Sen. Alan Lowenthal (D) announced a similar bill that would allow all state residents to stop companies from tracking their online activity.

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