Towergate Partnership is suing a broker for more than £300,000 over claims that he started up a rival firm after selling his business to the broking giant in January 2003.

The company is claiming damages from Danny Cooper for allegedly entering into arrangements with some of Towergate's top 50 clients, despite signing restrictive covenants prohibiting him from doing so.

According to a High Court writ, Towergate alleged Cooper had agreed that for three years after January 2003 he would not entice away customers or employees, or work in competition with the Towergate companies.

Cooper stayed on as an employee of Towergate, then Folgate Risk Solutions, after the acquisition, but left in August 2004 to set up Insurance Manager, an insurance management and consultancy firm. Insurance Manager's clients included Claremont & May and L&J Projects, both of which were clients of Towergate, it is alleged.

Cooper told Insurance Times: "We have been forced to counterclaim in an attempt to collect monies owed and set the record straight. Neither I nor my company have acted in breach of any agreements or done anything unprofessional or illegal."

Towergate also alleged Cooper had offered a job to Folgate's senior employee Kathryn Underdown and that he intended to employ her in order to compete with it.

Cooper added: "Kathryn had already decided she was leaving after Towergate tried to impose changes to her contract."

Towergate declined to comment on the case.