New York (CNN Business)The IRS is auditing Uber’s 2013 and 2014 tax bills, the company said in a filing Tuesday.

Uber’s (UBER) taxes are also under investigation by various state and foreign tax authorities.

Uber also said a decade’s worth of its taxes remain open across multiple jurisdictions, including the United States, United Kingdom, Brazil, Mexico, Australia, Singapore, Australia, India and the Netherlands. Those countries have not yet signed off on their tax bills from 2010, when Uber offered its first ride, through 2019.

Although Uber says it believes it has sufficient money set aside for any additional tax liability it could face, Uber acknowledged the timing of the resolution “is highly uncertain.”

The company did not have any comment beyond the filing. It did make the disclosure about the audits, which it termed an “examination,” in the filings it made ahead of its recent initial public offering.

Uber has not reported a profit, so it has paid very little in taxes. Losses can benefit Uber for tax purposes: A company can carry forward its losses to cancel or reduce the taxes it might have to pay in the future once it starts to make money.

Uber says it can apply about $5.1 billion in losses to offset US federal taxes and $4.4 billion for state taxes. But the company acknowledged that the investigation may reduce that tax benefit. Although the size and scope of the investigation make it impossible for the company to estimate how much its tax benefit could change, Uber said it is reasonably possible that the tax benefits of those past losses could “change significantly.”

Separate from the audits, Uber said it expects its carry-forward tax benefits to be reduced by at least $141 million, related to previous discussions with tax authorities.

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