A string of senior executive departures and hefty investment outflows since late last year has left Credit Suisse Asset Management's London unit in danger of suffering a rare downgrade from credit agency Fitch Ratings.

While asset manager ratings are based on long-term business strength and downgrades are therefore quite rare, Fitch has put its rating for CSAM's London investment management business on Rating Watch Negative, indicating that a downgrade could be on the cards in as little as six months.