B2B social network Xing is planning to introduce advertising for the first time before the end of the year, giving the company an extra revenue stream to add to subscriptions.

According to Xing, the targeted ads will only be introduced in certain sections and will “not compromise the usability of the website”. But it says the volume of ads will increase over the next year.

Xing, the first Web 2.0 firm to go public, currently has around 4m members. Though it is free to join and use, a number of members pay a subscription in return for premium features.

The network primarily serves the German-speaking world, with 1.2m members in Germany, Switzerland and Austria, but the company has recently extended into Spain, with the acquisition of Spanish social networks eConozco and Neurona.

It has also signed up to Google’s recently-announced OpenSocial API initiative.

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