The largest class-action lawsuit in German history is under way, with 17,000 irate shareholders of Deutsche Telekom (DT) out for revenge - and €80 million (£63.4 million).

Stakeholders in the monopoly who saw their shares tumble want compensation and answers.

A test case starts today in Frankfurt with a single shareholder seeking €1.65 million in damages.

The unnamed man has an army of 16,999 behind him and there is no shortage of high-profile witnesses due to take the stand, including ex-boss Ron Sommer and former supervisory board chairman Hans-Dietrich Winkhaus.

The process centres on the third tranche of DT shares released in 2000 which had a price of €66.50 or €63.50 for those who got in early. Demand was enormous, with the block of 200 million shares oversubscribed 3.5 times.

The shares hit a high of €103.50 on 6 March, 2000 - but after that it was all downhill. Since 2002, shares have not risen above €20.

Lawyers for the plaintiffs argue that data given to the stock exchange by DT on its real estate assets was highly inflated, and under German law that allows them to claim compensation, saying the shares were overvalued before they were floated.