The EU estimated a back taxes bill of 400 million euros for Amazon a year ago.

European Union regulators are about to order Amazon.com Inc. (AMZN - Get Report) to pay millions of euros in back taxes to Luxembourg, insiders told Reuters.

The order comes as the culmination of a three-year long investigation into whether Amazon received an unfair tax advantage based on a 2003 Luxembourg tax ruling. The 2003 ruling allowed an Amazon subsidiary to pay less in taxes there than other companies did.

The EU estimated a back taxes bill of 400 million euros for Amazon a year ago, but a revised figure is expected following conversations with other regulating bodies.

McDonalds Corp. (MCD - Get Report) and Engie SA (ENGIY) are next to face scrutiny over the same Luxembourg tax issue. At least 35 companies including Amazon and Anheuser-Busch Inbev (BUD) will pay back taxes to Belgium because of their participation in the illegal tax scheme.

Amazon is the latest company facing a tax order from European commissioners. Apple Inc. (AAPL - Get Report) , Starbucks Corp. (SBUX - Get Report) and Fiat Chrysler Automobiles (FCAU - Get Report) have all footed tax bills ordered by European entities recently.

Amazon stock traded up 0.19% to $961.04 mid-afternoon Tuesday.

Apple and Starbucks are holdings in Jim Cramer's Action Alerts PLUS Charitable Trust Portfolio . Want to be alerted before Cramer buys or sells AAPL and SBUX? Learn more now.

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