Facebook closed its acquisition of messaging app maker WhatsApp following approval of the deal by the European Commission late last week.

The deal sees WhatsApp co-founder and CEO Jan Koum join Facebook’s board. He will remain CEO of WhatsApp (which Facebook has said will remain a separate service) and receive a nominal annual base salary of $1, with restricted stock worth close to $2 billion.

The completion of the deal was confirmed by a filing with the US Securities and Exchange Commission.

Facebook and WhatsApp agreed the acquisition in February, with the total cost of the deal in the region of $19 billion. Today’s completion actually sees the deal now worth $21.8 billion, primarily because the value of Facebook stock has increased.

The European Commission (EC) gave the green-light to the acquisition at the end of last week, stating that the combined business “would continue to face sufficient competition”.

The Commission noted that WhatsApp and Facebook Messenger “are not close competitors”, with the former being based on phone numbers and the latter closely related to profiles on the social network.

The EC also noted that while it was able to analyse potential data concentration issues with regard to the impact on the online advertising market, “any privacy-related concerns flowing from the increased concentration of data within the control of Facebook as a result of the transaction do not fall within the scope of EU competition law”.

Following its approval of the deal in April, the US Federal Trade Commission talked tough with regards to user privacy. While leveraging user data would be an effective way of helping monetise WhatsApp, it would also go against much of what the company has previously said it stands for.

According to earlier reports, it was Facebook itself that requested an EU review, in order to avoid the possibility that it may become involved in multiple, separate actions across different European countries.

It is believed that stakeholders including mobile operators, social networks and internet service providers were consulted by the European regulators.

Mark Zuckerberg reportedly said in September that WhatsApp can reach two to three billion users once it becomes part of Facebook. The Facebook CEO said WhatsApp is likely to benefit from access to Facebook’s resources and its audience of 1.3 billion monthly active users.

The most recent figure for WhatsApp’s user base was given in April, when the number of monthly active users passed the 500 million mark.