Group chairman Lukas Muehlemann say the changes are not linked to recent regulatory enquiries

The bank has insisted that the departure on Thursday of CSFB chief executive Allen Wheat has nothing to do with the regulatory enquiries it faces.

Allen Wheat is to be replaced by John Mack, a former president of Morgan Stanley Dean Witter.

Further details on the changes will become available at the half-year results press conference on 29 August.

Tough times

The changes affect other parts of the Credit Suisse group as well but are expected to be felt most at CSFB.

The dot.com crash and fears of a US slowdown have seen investment bankers tighten their belts worldwide.

Indeed, in the US, CSFB earned fat commissions from technology companies selling their shares on the stock market for the first time.

This helped place the Swiss bank at the top of the league tables for technology deals.

But now, this reliance on technology commissions has unsurprisingly seen it hit by the slowdown in that sector.

And in its recent results it warned of a challenging year ahead.

Change in structure

The bank's plan is to tighten the chain of command, cutting the four operating units of its business to two.

CSFB's US operation has also been the target of official enquiries

This new structure is more in line with that used by banks elsewhere and may leave it better placed to manage its 28,000 staff.

In June, chairman and chief executive Lukas Muhlemann told the group's annual meeting in Zurich that improving CSFB's controls and internal processes was now "top priority".

He admitted that the company's big increase in size had been a problem - its investment bank staff tripled last year - which many believe has let the bank's controls lapse.

There is however a view that it lacks the political clout of some of its competitors, so is more likely to face regulatory scrutiny.

Regulators list

But, the list of regulatory inquiries is long and not confined to just one country.

CSFB has been subject to an investigation by the US authorities since late last year.

The Securities and Exchange Commission are investigating whether staff took part in kickback schemes with clients so they could get more shares at initial public offerings. CSFB fired three technology brokers at the end of June.

In India, CSFB became the first foreign bank to be banned from stock broking, following an investigation into share rigging.

CSFB, which acted for a broker who has been arrested in connection with a bank fraud, denies acting improperly.

In the UK, it hit the headlines when it sacked three traders from the so-called Flaming Ferraris, a group of dealers named after a Fulham cocktail.

James Archer, son of millionaire author Lord Archer, was one of those involved. The scandal centred on allegations of manipulation of shares in the Swedish firm Stora.

The Flaming Ferraris were famous for working hard and playing hard, hiring limousines to travel around town and even paying caterers to supply a mountain of whipped cream for a huge food fight.

Tokyo obstruction

The Swiss bank also suspended some of its employees for obstructing an inquiry in Tokyo by Japanese financial regulators.

The Japanese authorities suspected the bank's local subsidiary of offering clients inappropriate products, such as risky derivatives contracts that could have helped them conceal huge losses by bouncing them from one account to another.

In this case, the Japanese government was determined to make an example of CSFB because of its prominent position in international financial markets and the government's own reputation of lax banking supervision.