A group of German investors are planning to sue three global ratings agencies after losing their investments in top-rated Lehman Brothers shares.

The case against Standard & Poor’s (S&P), Moody’s and Fitch Ratings is the first of its kind in Germany and follows similar court proceedings in the US.

The legal stoush follows international moves to tighten regulation of ratings agencies, held partially responsible for the credit crunch in 2008 when shares given top billing – such as Lehman – later folded.

An initial test case against S&P is being brought by one German investor, who lost €30,000 on A+ rated Lehman certificates in September 2008.

The lawsuits against Moody’s and Fitch are expected to be filed in the next few weeks.