Fortis Investments, the funds arm of the Belgo-Dutch banking group in merger talks with ABN Amro, has joined a trickle of traditional asset managers following their hedge fund peers by launching a strategy that involves shorting stocks.

The 130/30 strategy, which allows managers to short-sell up to 30% of their portfolio to enable them to fully exploit negative views on stocks, has traditionally been the preserve of managers with quantitative research styles, which use computer models to identify the best investments.