British firms are a third more likely to come under pressure than their European counterparts, according to the latest “activist alert” report from consultant Alvarez & Marsal.

The model – which has a 58pc success rate at identifying activist targets – has identified 54 vulnerable UK firms, up from 52 the last time the study was conducted three months ago.

There were also “early indications” that increasing the number of women on a board could reduce the risk of shareholder activism, the report found.

This summer demonstrated the power activist shareholders can wield when FTSE 100 mining giant BHP Billiton cracked under pressure from Elliott, adopting plans to offload its US shale and gas business, which the investor had been calling for.