Seymour Pierce, the largest adviser to companies on the junior AIM stock exchange, has been handed a record £400,000 fine and publicly censured by the market's disciplinary committee.
AIM said Seymour Pierce twice failed to meet standards required by a nominated adviser. In one case it failed to inform a client company it should tell the market it was in financial difficulties. In the other it failed to carry out full background checks on a director in a company planning to list on AIM.
New chief executive Phillip Wale said: "We have put in place major changes and are confident our systems and procedures are now of the highest standard."