The relatively unknown investment fund where Theresa May’s husband Philip works as a senior executive is one of the world’s largest and most powerful financial institutions, controlling $1.4 trillion in assets.

Its portfolio also includes $20 billion of shares in Amazon and Starbucks, both of which were cited by the Prime Minister-designate in her pledge to crack down on tax avoidance yesterday.

Latest filings to US authorities show that Los Angeles based Capital Group owns huge stakes in a variety of companies, including investment bank JP Morgan Chase, defence giant Lockheed Martin, tobacco company Philip Morris International, the pharmaceutical sector’s Merck & Co, and also Ryanair.

The company, which has a low profile outside the financial sector, has confirmed that Mr May, a pension fund expert, works out of its Mayfair office in London, with a spokeswoman telling The Independent: “Philip is a client relationship manager who stays in contact with organisations and institutions in the UK to ensure they are happy with the service being delivered by Capital Group and that we understand their goals. Philip is not involved with our investment research or portfolio management activities.”

Who is Philip May?

However, the company he works for has benefited from its investments in the likes of Amazon and Starbucks, both of which have been criticised for tax avoidance structures and which were mentioned by Ms May as she outlined her manifesto for Downing Street yesterday.

She said: “We need to talk about tax. It doesn’t matter to me whether you’re Amazon, Google or Starbucks: you have a duty to put something back, you have a debt to your fellow citizens, you have a responsibility to pay your taxes. So as Prime Minister, I will crack down on individual and corporate tax avoidance and evasion.”

Capital International's office in London (Google)

It is not clear whether she was aware that her husband’s company was such a significant investor in the Amazon and Starbucks.

According to latest filings on 31 March this year, Capital Group, through its various divisions and funds, including Capital World Investors and Capital Research Global Investors, owned at least 32 million shares in Amazon, worth about $20bn.

5 tax avoiding companies in the UK Show all 5 1 /5 5 tax avoiding companies in the UK 5 tax avoiding companies in the UK Facebook Facebook paid £4327 in corporation tax in 2014, after it made a pre-tax loss of £28.5 million, according to filings at Companies House. That's less tax that new average UK employee pays on their salary. 5 tax avoiding companies in the UK Amazon Amazon’s UK business paid just £11.9m in corporation tax last year, even though the online retail giant took £5.3bn in sales from British shoppers. 5 tax avoiding companies in the UK Google So well known for avoiding tax that it had the 'Google tax' on multinationals that move profits to low-tax countries named after it. Alarm bells started ringing in 2012, when Google revealed it payed only £11.6 million to the Treasury, despite taking £3.4 billion in the UK. 5 tax avoiding companies in the UK Uber Uber paid £22,134 in UK corporation tax last year despite making an £866,000 profit. 5 tax avoiding companies in the UK Starbucks In October, the European Commission ruled that Starbucks' tax deal in the EU was illegal, ordering it to pay pay between €20-30 million to the Netherlands.

Its 6 per cent stake made it one of Amazon’s biggest shareholders.

It also owned about $2bn of Starbuck shares at the end of March when the total assets under its management was $1.4 trillion.

Other shareholdings included at least $7bn in JP Morgan Chase, $9bn in Philip Morris International, $5bn in McDonald’s, $6.6bn in Lockheed Martin, and $1.5bn in Ryanair.

A source close to Ms May said: 'She said in her speech that these companies have a duty to put something back. That is her strong view and it remains her strong view.'

It is not clear which clients Mr May deals with on behalf of Capital Group, but his name has been mentioned in the minutes for Norfolk County Council’s pension committee reports, where he has appeared on behalf of his company as a pension manager.

A spokesman for Starbucks said: “We pay all our taxes in the UK and in 2014 we moved our European Headquarters to London. Last year we paid £18m in corporation tax.”

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