Germany's biotech stocks have been trapped in the Neuer Markt meltdown since the end of July last year, with 10 biotech listings tracked by BioCentury falling some 70% in aggregate through last week. The meltdown, in which the Nemax 50 Index has plunged 80%, combined with media talk earlier this year of fraud involving high-profile blowups of stocks outside the biotech space, has led some market watchers to question the sustainability of the high tech exchange.

Indeed, even though the growth stock exchange in its early years touted its criteria for ensuring the quality of its listings, the Deutsche Boerse now is moving to tighter listing rules that will purge the wreckage. The parent exchange has announced that starting Oct. 1, the new market will delist penny stocks and insolvent companies (see BioCentury, July 23).