A new study by the Institute for Family Business has revealed the UK's 10 largest family businesses.
The list is headed by the Weston family-owned Associated British Foods, which had 2009 sales of £9.26 billion and includes well-known high street brands such as Kingsmill, Pataks, Primark, Ryvita and Twinings.
ABF was founded by Toronto-born W Garfield Weston in 1935. Today, the Weston family controls ABF through family holding company Wittington Investments, which also owns the luxury food store Fortnum & Mason and Heals.
Third generation George Weston, 46, is currently chief executive of ABF.
All the companies on the list have sales in excess of £1 billion and cover a wide range of sectors from heavy industry and construction to media and IT.
Grant Gordon, IFB director general, said: "With sales totalling some £36 billion and with tens of thousands of employees, these companies show that family businesses are some of the heavyweights of UK plc.
"These firms sit in the vanguard of the family business sector that contributes over 30% of GDP and which is playing a vital role in driving the entrepreneurship needed to get our nation back on track towards economic recovery."
Top 10 UK family businesses 2010
1 Associated British Foods (Weston family, 2009 sales £9.26 billion)
2 Stemcor (Oppenheimer family, sales £3.54 billion)
3 Swire Group (Swire family, sales £3.24 billion)
4 European Metal Recycling (Sheppard family, sales, £3.10 billion)
5 Laing O'Rourke (O'Rourke family, sales £2.50 billion)
6 SCH (Rigby family, sales £2.32 billion)
7 Arnold Clark Automobiles (Clark family, sales, £2.21 billion)
8 Daily Mail & General Trust (Viscount Rothermere and family £2.12 billion)
9 JCB (Bamford family, sales £2.01 billion)
10 Bestway Group (Pervez family, sales £1.90 billion)
According to the IFB, a firm qualifies as a family business if: the majority of votes are held by the person who established or acquired the firm or their spouses, parents, child or child's direct heirs; and at least one representative of the family is involved in the management or administration of the firm.
In the case of a listed company, the person who established or acquired the firm or their families possess 25% of the right to vote through their share capital and there is at least one family member on the board of the company.
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