Credit Suisse investors suing Swiss regulator after £4bn bond wipeout

The Swiss financial regulator’s decision to trigger a ‘complete write-down’ of Credit Suisse AT-1 bonds was part of the emergency merger with UBS. Photograph: Fabrice Coffrini/AFP/Getty Images

A group of Credit Suisse investors who lost bonds worth more than CHF 4.5bn (£4bn) are suing Switzerland’s financial regulator over a decision to wipe out risky bank debt after an emergency merger with UBS last month.

The investors filed their claim at a court in St Gallen, in the north-east of Switzerland, weeks after Swiss authorities orchestrated the takeover of Credit Suisse by its larger rival UBS, to try to stem a crisis of confidence in the global banking sector.