Hedge funds are boosting their short bets on Royal Mail, which has suffered a series of setbacks this year culminating in the shock departure of the chief executive.

Some big name asset managers have also piled in. BlackRock and Pictet joined hedge funds Egerton Capital and Adelphi Capital in building up short bets against Royal Mail, according to the Financial Conduct Authority’s register of short positions. The regulator follows many European watchdogs in disclosing positions that make up more than 0.5% of a listed company's outstanding shares.