Before the emergence of the international network, BDO Seidman LLP was founded in 1910 by Maximillian Seidman as Seidman and Seidman in New York.

The global organisation of individual BDO firms across the world became BDO International in 1963, and is now a global network of professional accountancy firms with 612 offices in 107 countries.

With more than 30 000 partners and staff, the network rakes in $3.911bn, leaving the firm firmly in the fifth pole position internationally.

Like the Big Four, member firms are independent legal entities operating under their own firm names.

The largest firms include BDO Kendalls in Australia, BDO Deutsche Warentreuhand in Germany, BDO Camps Obers in Holland, BDO Dunwoody in Canada, BDO Seidman in the US and BDO Stoy Hayward in the UK

The UK firm began life as Stoy and Co founded by Fred Stoy. In 1919, Jack Hayward joined and it became Stoy Hayward and Co.

Several mergers later with Finnie and co in 1992 and DO Binder Hamlyn in 1994 created BDO Stoy Hayward, which then become a member of the BDO International network.

It also became a limited liability partnership in 2002.