Concerns have been raised that the SMC Group misled its stockbroker as to the firm's profit-making potential.
London-based stockbroker Numis Securities has been an adviser to the SMC Group since last summer and, according to a source close to SMC, profit projections posted to the City were too ambitious.
The allegation comes in the wake of founder Stewart McColl's shock departure from the firm following disappointing trading results.
McColl's right-hand man, business-development director Gordon Watson, also stepped down from the company's board in the shake-up The source told the AJ: 'The projections we made on our profits were just crazy - that's why we were crucified when we didn't deliver.
'We misled the broker with the profit projections that we had established - that must have been what happened.
We should have been more sensible with the figures we were projecting.'
In June 2005, SMC became only the second UK architecture firm to be listed on London Stock Exchangesubsidiary the Alternative Investment Market, joining Aukett Fitzroy Robinson.
SMC had a record first year as a quoted company, prompting the firm to acquire nine businesses, including Will Alsop's practice.
The firm captured the attention of the profession, suggesting that big business could be applied to the world of architecture.
But, according to the insider, by adding the profits of the nine acquired firms to SMC's own, the group gave an over-ambitious projection of potential profits.
Under McColl's leadership, SMC become the secondbiggest architecture firm in the UK, ranked below only BDP in this year's AJ100, which measures firms on the number of architects they employ.
'There was nothing wrong with the strategy, ' the source said. 'What we established was a very solid business plan. The strategy of consolidation in architecture practices can be a successful model.
'But it transpires that there has to be a scapegoat, and he [McColl] has been made that scapegoat.'
The insider also said there are rumours that SMC's low share price may now prompt a takeover bid.
McColl is said to be 'gutted' by his departure from the company he founded in 1996. He refused to comment on his resignation but said he planned to return to the industry.
'I am definitely not retiring, ' said McColl. 'There is no doubt that I will be returning to architecture.'
SMC and Numis have rejected claims that anyone was misled. A spokesman from their public relations firm, Bell Pottinger, said: 'Both parties believe that there is no truth to this at all. It is completely unfounded.'