ISTANBUL (April 13): Istanbul’s stock exchange is delighted to be attracting the attentions of a mysterious trader known locally as “The Dude.”

“This ‘Dude’ is buying from our market, why should we be concerned? He is doing good stuff,” Borsa Istanbul AS Chairman and Chief Executive Officer Himmet Karadag told Bloomberg in a Wednesday interview.

The trader first came to prominence in early 2016, when locals started noticing a series of massive bets dictating the direction of the Turkish stock market. On Monday, for instance, Borsa Istanbul data show that buy orders through a single brokerage favored by the unknown investor were responsible for almost half of the day’s total.

Turkey’s benchmark stock index was the best performer in the world that day, rising more than 3%.

Karadag said the bets’ origins had been investigated by Borsa Istanbul, which found no manipulative intent. “‘The Dude’ is making reasonable and profitable investment decisions,” said the CEO, who’s also on the board of the government’s new wealth fund.

High Frequency

Karadag attributed last year’s “Dude”-linked trades to a foreign fund that he declined to identify. “We don’t know the investors of the fund or whether it is the same one this year as well,” he said.

The trader uses high-frequency and algorithmic trading strategies that will become a more common feature of the nation’s US$186 billion equity markets, Karadag said. They make up 18% of activity at the Borsa Istanbul, a share he expects to climb over 50% in the next three years.

“Get used to these dudes,” he said.

Yes Vote

Istanbul-based brokerage Yatirim Finansman, which “The Dude” is widely suspected to use to execute trades in Turkey, has stood out as handling the largest trades on many of the market’s most volatile days.

The firm was also a net buyer of 208 million liras ($79.5 million) of Turkish equities on Monday, when the Turkish index beat its peers. On that day purchase volumes exceeded that at the second-busiest brokerage on the day by almost three times.

For Karadag, Monday’s moves evince a market buying into the prospect of ’yes’ victory in Sunday’s referendum, where citizens vote on whether to hand President Recep Tayyip Erdogan sweeping new powers.

“‘The Dude’ may have figured this out earlier and started buying,” Karadag said.