'Flash Crash' trader's ex-colleague: 'He wasn't spending any money, he was the biggest guy here and I thought he was the cleaner'

Trader screenREUTERS/Brendan McDermidA trader looks at his screen while working on the floor of the New York Stock Exchange June 24, 2014

Navinder Singh Sarao, the prop trader arrested Tuesday in connection with the “Flash Crash” in US stocks in 2010, has hit headlines hard this week.

UK tabloids have dubbed Sarao “the Hound of Hounslow” with US regulators alleging he raked in more than $US800,000 (£530,000) per day at times.

But what was he really like in person?

Business Insider spoke to two people who worked alongside Sarao at Futex before 2010. They painted a picture of a calm individual trading enormous amounts with impressive skill, but with no obvious trappings of wealth.

One trader who worked at Futex before the “Flash Crash” says Sarao was completely unassuming. “When I was first there someone that was in the know told us he had $US13 million back in 2009 — so I’d be surprised if he didn’t have more than $US40 million now. He would clear $US400-500 thousand per week, and this was seven years ago.”

“It’s totally true about him not spending money. My first impression of him when I got here and people told me he was the biggest guy here, I thought they were having me on. I thought he was the cleaner.”

“He was very odd, a very strange personality — somebody said that he used to come in late to avoid the train fare but he used to come in at around 2, because that’s when the S&P opened and that’s mostly what he traded.”

The Times had reported a former colleague making similar comments about Sarao coming to the office late.

“He had three screens on his desk when most people had maybe six, and he was just absurdly fast,” the trader told Business Insider.

According to the source, Sarao left Futex in 2009 before the Flash Crash, but he was making more money than anyone else in the building: “When someone’s making the most amount of money you tend to watch them, and I think the management were a little bit nervous. He wanted to push and push and push.”

That aligns with the records of Nav Sarao Futures Limited, the firm he set up — which show negligible turnover in the 2007, 2008, and 2009 financial years, followed by a boom to £6.67 million in turnover in 2010. Turnover peaked above £10 million in the 2012 filings.

Simon Maelzer of MacroVIGILANCE.com, who worked with Sarao at Futex in 2008, told Business Insider:

My main memories of him are of a very focused guy who sat alone at a separate part of the office. He would wear headphones to create his own sound environment as there was often a lot of shouting and some bad language coming from various other traders as emotions flared when market moved aggressively.

He always seemed calm, collected and very much in “the zone” like an elite athlete. You could never tell if he was winning or losing, just in complete control like a world class poker player.”

Business Insider has been unable to reach two former directors mentioned in Nav Sarao Futures Limited’s regulatory filings — Miles MacKinnon (terminated in October 2010) and Gurmatpal Singh Dusanjh (terminated from the company September 18, 2012).

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