"Under Armour is cooperating with the US Securities and Exchange Commission and the US Department of Justice investigations", a company spokesman said on Sunday night, as quoted by The New York Times.
Earlier on Sunday, The Wall Street Journal reported that a federal investigation, which has not been made public, is being conducted to figure out whether the company could have shifted its sales from quarter to quarter to mask its slowing growth and appear "healthier."
"The company began responding in July 2017 to requests for documents and information relating primarily to its accounting practices and related disclosures, and the company firmly believes that its accounting practices and disclosures were appropriate", an Under Armour spokesman said in a Sunday statement, responding to the Wall Street Journal report.
The sportswear manufacturer has seen multiple leadership changes in the past three years amid declining sales.