BILL GATES is a man of two public images — the ruthless, monopolistic capitalist and the philanthropist who has given away a large chunk of his fortune to good causes.

While over the past decade Microsoft has been fighting off rivals in the courts as it tries to cling to its dominant position, Mr Gates has been seeking to advance vaccination against deadly diseases in the Third World.

The Bill & Melinda Gates Foundation, now the biggest charitable foundation in the world, was set up nearly 12 years ago, just as the Microsoft chairman was fighting a swath of antitrust law suits that were attempting to break up Microsoft’s monopolistic position.

Mr Gates established the foundation in 1994 with the help of his father, William H. Gates. At that time it was endowed with $94 million to fund educational projects.

Three years later, at the beginning of the dot-com boom, when Netscape, the internet search engine, was fighting Microsoft for dominance of the internet, the foundation began to campaign about the lack of availability of drugs for poorer nations — a stance that, ironically, attacked the dominance of the world’s biggest drug companies.

Since 1997, the foundation has grown at an astronomical rate — it now employs 250 people and has an endowment of $28.8 billion (£16.5 billion). It supports causes across all states in America, including supplying nearly 50,000 computers to 11,000 libraries, and aids medical work and vaccination efforts in more than 100 countries.

Meanwhile, Microsoft’s competitors largely have failed in their attacks on the company’s dominant market position.

In 2003 Microsoft agreed to pay £545 million to AOL Time Warner, the ultimate owner of Netscape, to settle their dispute. In 2001 a federal appeals court finally upheld an antitrust settlement between Microsoft and the Justice Department, which ended efforts of rivals to break up the software giant.

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