Turkey Targets Brokerage Founder in Alleged $18bn Ponzi Scandal

Istanbul, 24 September 2026 — EBM Newsdesk Analysis — By Anthony Gill

Turkish authorities arrested Emre Tezmen, founder and chairman of brokerage Tera Yatırım, on Wednesday morning, along with four other executives, as part of a widening investigation into what officials have described as a “Ponzi-like” investment fund scheme. Turkey’s Capital Markets Board has ordered the liquidation of roughly 130 funds worth $18.3bn, affecting more than 450,000 investors who now face a wait of up to six months to learn how much of their money, if any, they’ll get back.

How the Scheme Actually Worked

The mechanism at the centre of the collapse is a specific and fairly elegant form of self-dealing. The affected funds, run through Tera Portföy and Pusula Portföy among others, concentrated their holdings in shares that were rarely traded. With so few shares actually available on the market, even modest buying by the funds themselves was enough to push prices up. Those inflated valuations then flattered the funds’ reported returns, which in turn drew in new savers — and their cash was funnelled into buying the same or related illiquid stocks, reinforcing the cycle further. It’s a structure that can run indefinitely as long as new money keeps arriving faster than existing investors try to withdraw. It stopped working on 16 September, when Tera Yatırım’s fund-management arm reported it had failed to make payments to investors withdrawing from two of its funds.

The Scale of the Response

What followed was one of Turkey’s largest financial-crime crackdowns in years. Sixty suspects now face legal proceedings, 51 people have been barred from leaving the country, and detentions have swept up figures well beyond Tera itself — including Pusula Holding chairman Serdar Turhan, Pusula Portföy chairman Muhammed Yarız, and Destek Yatırım chairman Altunç Kumova. Two of Tera’s board members, Kerem Alkin and Emre Alkin, were also detained; Kerem Alkin previously represented Turkey at the OECD and sat on the boards of state-owned Halkbank and Turkey’s sovereign wealth fund, while his brother Emre is a well-known television economist and university rector — a reminder that this scandal reaches into genuinely established financial and institutional circles, not a fringe operation. Investigators are examining allegations of aggravated fraud and participation in a criminal organisation. Al-Monitor has already drawn comparisons to Bernie Madoff, reflecting how the case is being read internationally as much as domestically.

Markets Reacted Immediately

The Borsa Istanbul All Shares index fell 12% in the space of a week, with roughly 50 individual stocks losing 40% or more of their value, and the benchmark BIST 100 dropped as much as 6-8% on the day the scandal broke, triggering temporary trading halts. Finance Minister Mehmet Şimşek moved quickly to contain the fallout, putting the total fund value at $18.3bn and stating he does not expect the crisis to spread across Turkey’s wider financial markets, noting the affected funds represent only about 10% of the sector. “We have placed the problematic area under quarantine,” he said. Goldman Sachs data suggests some of that containment message is landing: lira deposits actually increased by roughly $12bn in the week to 15 September, even as the scandal was breaking — savers appear to be rotating into cash rather than fleeing the currency entirely, a genuinely different reaction than a full-blown confidence crisis would typically produce.

The Question That’s Actually Damaging

The detail likely to cause Turkish regulators the most lasting reputational damage isn’t the scheme itself — it’s the timing of what they knew. It has emerged this week that Istanbul prosecutors sent a letter to the Capital Markets Board as early as February 2025, asking it to investigate unusual share transactions linked to Muhammed Yarız, more than eighteen months before the scheme finally collapsed. That gap is the part investors and international observers will be watching most closely, because it raises a harder question than any individual fraud case does: whether Turkey’s capital markets regulator had the information needed to intervene far earlier, and simply didn’t.

Where This Goes: An $18bn fund collapse affecting nearly half a million people is a serious domestic crisis on its own terms, but the more consequential story for Turkey’s markets may be the eighteen-month gap between the first prosecutorial warning and the actual liquidation order. Şimşek’s “quarantine” framing may well hold — deposits rising rather than fleeing is a genuinely reassuring early signal. But the question of what the SPK knew, and when, is the one that will determine whether international investors treat this as an isolated fraud case or as evidence of a regulator that watches its own warnings and waits.