Is this Australia’s secret billionaire?

The best performing investment fund in the world is a small fund in Sydney called Mathews Capital, run by a former stockbroker named Phil Mathews.

Mathews and his fund are currently being whispered about in hushed tones in cafes around Sydney. Some say he is Australia’s secret 39th billionaire. Others that he has made one of the world’s biggest oil futures bets this year, producing a return of 80% for his investors in May alone.

I tracked Phil Mathews down to his Sydney office, and it would be fair to say that the phrase “a private person” was invented for him. It would easier to interview a rock.

Apart from the rumours about him that have been buzzing around Sydney lately, my eye had been caught by a substantial shareholding notice that popped up on Business Spectator this week, saying: “Mathews Capital Partners bought 30,472,664 Santos shares between June 2, 2005 and May 27, 2008, becoming a substantial shareholder with 5.12%.”

That stake in Santos is worth $660 million. Mathews told me this morning that his main fund – called the Sabre Fund – totals $2 billion, and there are two others in his stable worth a total of $1.5 billion, called the Tomahawk Fund and the Velocity Fund.

So he has a third of his main fund in Santos. This is a man who likes a big bet.

According to other recent substantial shareholder filings, Mathews also owns 19.6 million shares in Nexus Energy, 15.4 million in Arrow Energy, 9.6 million in Metgasco and 6.5 million in Pure Energy. On top of that he also owns 93 million shares or 10.5% of Renison.

I make that another $122 million invested in gas, on top of the Santos play.

Mathews says his fund is basically an energy fund, and that he started progressively moving out of industrials in 2004.

He would only say two things about his performance before clamming up – that his investment return for the period since 1 July 2007 has been 210%, and that Bloomberg has described Mathews Capital as the world’s best performing fund over one, three and five years.

I couldn’t find that reference, and Mathews wouldn’t say what his one, three and five year performances have been, but I think we can assume it’s true. It has certainly been a very good time to be an energy fund.

He wouldn’t comment on the stories about a big oil futures bet, but one thing we know for sure; he is making a massive bet on coal seam gas.

“It’s bigger than the Bass Strait,” he told me. “Santos has 100 trillion cubic feet, which is equivalent to 40 billion barrels of oil. 40 billion barrels! That’s bigger than that new oil discovery off Brazil.”

And, yes, in case you were wondering, Sabre Fund has been closed for 18 months, but the Tomahawk Fund and the Velocity Fund are still open.

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