Zuckerberg also received questions on anti-trust issues, an area where Europe has become increasingly proactive in recent years. On whether Facebook is a monopoly, he responded that there are plenty of new competitors in the space with "tens of millions of users." Incidentally, Facebook has 1.6 billion active users which puts it in a completely different stratosphere to these so-called competitors. But more relevantly, if Facebook is deemed a monopoly, then what is to stop regulators from breaking up its other businesses (i.e. WhatsApp, Instagram…)?

Taxation is another area that featured prominently. The European Commission has recently proposed a digital tax for companies whose users are based in Europe. While the tax is under discussion, the feeling from many politicians and lawmakers is that mega tech companies are not being taxed adequately given the size of their revenues. When asked about taxation in the testimony, Zuckerberg responded that "Facebook has always paid taxes in all of the countries where we have operations set up. We pay all taxes required by law and we invest heavily in Europe." This prompted one MEP from the Greens party, Terry Reintke, to quip: "We urgently need stricter regulation on taxation. EU-wide. Now"

The visibly uncomfortable Zuckerberg continued his trip in Paris later in the week where he met with French President Emmanuel Macron alongside other key figures in tech. And while he may receive a slightly less hostile welcome there, taxation is also expected to feature high on the list of topics as well.

But this is most definitely not the last time Zuckerberg will have to respond to questions on the continent. If the purpose of this tour was to stop Europe from being worried about Facebook, the exact opposite has occurred: Facebook should be worried about Europe.

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