Reuters Microsoft said on Wednesday the U.S. Internal Revenue Service IRS in September notified the company that it is seeking an additional tax payment of 28.9 billion, plus penalties and interest for tax years from 2004 to 2013.

Microsoft said the IRS notices relate to an ongoing dispute between the company and the U.S. tax authority, which is auditing how Microsoft allocated its profit among different countries and jurisdictions.

The Redmond, Washingtonbased company said it has since changed its practices so that issues raised by the IRS are relevant to the past but not to our current practices, according to a Microsoft blog.

Microsoft said it believes that any taxes owed after the audit would be reduced by up to 10 billion based on tax laws passed by former President Donald Trump.

The company said it disagrees with the IRS39;s findings and plans to dispute them, first in an internal IRS proceeding and then later, if necessary, in courts.

The IRS told Reuters it is prevented by U.S. law from confirming or denying whether it is auditing any taxpayer.

Reporting by Samrhitha Arunasalam in Bengaluru and Stephen Nellis in San Francisco Editing by Deepa Babington and Matthew Lewis

Source Reuters