Biotech Amgen Inc. is in a pitched battle with the Internal Revenue Service over the company’s international tax strategy and $10.7 billion in back taxes and penalties that the agency says it is owed.
The IRS says that Amgen underreported its taxable income by nearly $24 billion from 2010 to 2015 by inappropriately attributing what the agency says should have been U.S. profits to a Puerto Rico subsidiary that oversees manufacturing of the company’s drugs.
