Activist investor Julian Treger has raised his stake in self-storage company Lok’nStore to 12.6%.

Through his vehicle Audley Capital Management Treger today revealed he had increased his shareholding from 2.66m to 3.38m shares for the Audley European Opportunities Master Fund.

Treger bought the shares on Monday, when Lok’nStore’s share price closed at its lowest price since November last year of 195p. The shares now stand at 198p, which values it at £53m. Lok’nStore is 29% owned by chief executive Andrew Jacobs and chairman Simon Thomas.

Treger built up a reputation as someone who rattles cages at Active Value Advisors, the aggressive fund manager that he co-founded with fellow South African Brian Myerson.

For the next decade chief executives would shiver at the thought of a call from Treger and Myerson. At a time when few people had heard of hedge funds, they described themselves as the ‘Rentokil of fund management’. They agitated for change at companies as diverse as Liberty, the department stores; Scholl, the footcare specialist; and the former Ratners jewellery chain Signet, by buying up stakes and lobbying management.

It also launched an audacious £275m hostile takeover of Hogg Robinson, the travel group, and tried to stop Cordiant, the advertising group, from being sold to WPP. Neither move was successful.

After splitting amicably in 2004, Myerson set up Principle Capital, which he floated on AIM that year, and Treger founded Audley Capital.