XING, Europe’s LinkedIn, has acquired kununu, Europe’s Glassdoor, for up to 9.4 million euros ($12.3 million).

Kununu is an employer assessment and review platform that enables people to rate their jobs and the company they work for. The service is available in Germany, Austria and Switzerland, and Vienna-based kununu claims its platform currently boasts close to 250,000 reviews.

Founded in 2007, kununu says it’s currently registering around 3 million page impressions per month.

XING is coughing up 3.6 million euros for the acquisition but says additional payments totaling around 5.8 million euros could follow, depending on future performance.

The possible earn-outs will be paid by February 2015, XING says (press announcement in German).

Thomas Vollmoeller, XING’s CEO, had this to add:

“XING is already Germany’s market leader when it comes to social recruiting. Our acquisition of kununu will significantly boost our position within this growth market. By uniting forces, kununu and XING can provide unique insights into companies.

We can also help businesses to improve their image and, with it, their chances in the battle for top talent. This is underlined by the fact that public employer reviews by their employees render long-term employer branding as absolutely essential.”

XING had been a partner of kununu for the past two years.

The latter company’s founders, Martin and Mark Poreda, will stay as kununu’s managing directors. XING says no changes will be made to the kununu brand or portal, and that its 30 staff will all retain their jobs.

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