Here's what you need to know about Margrethe Vestager, the politician going after Apple

Margrethe Vestager is a corporation's worst nightmare.

The antitrust enforcer recently ordered Apple to pay up to 13 billion euros in taxes as part of a broader crackdown on tax avoidance in the Eurozone. Past campaigns include Starbucks in the Netherlands and Amazon in Luxembourg.

"Europe is open for business, if you want to do business, but maybe not so open if you want to come for tax avoidance," she said on Bloomberg TV on Tuesday.

By slamming Ireland for providing illegal incentives to Apple, Vestager is likely to ignite one of the world's biggest tax disputes and strain relations between Europe and the US.

Vestager graduated with an MS in economics at the University of Copenhagen in 1993, and then took a job at the Danish ministry of finance. At 30, she was appointed minister for education and ecclesiastical affairs, before becoming a member of Parliament with the Social Liberal Party, aka Radikale.

At 39, she became the political leader of that party before becoming EU competition commissioner in 2014.

She has waged high-profile battles against multinationals. She has launched her third set of antitrust charges against Google, with the latest on the internet giant's advertising business. She's also turned her fire on Russian energy giant Gazprom for unfair pricing in Eastern Europe.

She favors ambassadors who "truly embrace social media," and frequently tweets about case rulings and the current political state. She lamented Britain's decision to leave the EU, and lauded Hillary Clinton as the first female US presidential nominee.

Vestager is also known for her punchy wit. When her opposition slammed her spending plan, Vestager expressed caution toward "any judgment on size from men," according to a profile by the Financial Times' Christian Oliver and Alex Barker.