A liquidity default at a cluster of portfolio management firms triggered the sharpest BIST 100 drop since May, criminal complaints against fund managers, and an emergency meeting of Turkey's Financial Stability Committee before markets opened.
Turkish equities have just lived through their worst 48 hours since May. On 16 September, the BIST 100 index shed 5.54 percent to close at 13,122.58 points, tripping circuit breakers and freezing trading for ten minutes as bank shares led a broad, indiscriminate rout. The proximate cause was not macroeconomic — it was a default. Pusula Portföy, a mid-sized portfolio management firm, announced it could not meet redemption requests on several of its funds, most critically its "PRY" money market fund, which was pulled from purchase on the TEFAS trading platform. Within hours the contagion had spread to Tera Group, the firm in the process of acquiring Pusula's holdings, and to Katılımevim, a savings-finance company with more than 102,000 active members whose shares have lost roughly half their value in a month.
By Thursday morning, before the market opened, Finance Minister Mehmet Şimşek convened the Financial Stability Committee to declare the problem "temporary and manageable" and insist there is no structural risk to Borsa İstanbul. The Capital Markets Board (SPK) followed with the heaviest intervention of the episode: trading was frozen in all TEFAS-listed funds of seven portfolio firms, dozens of funds were ordered liquidated, minimum margin requirements were eased to slow forced selling, and two-year trading bans and criminal referrals were issued against named fund managers. Financial police searched brokerage offices in Istanbul and detained a holding-company chairman. What began as a niche fund-liquidity problem is now a full-blown regulatory and criminal investigation running in parallel with an effort to calm the index.
Below, five questions to make sense of what is a fraud story wearing a market crisis's clothes — and what it says about the credibility test facing Turkey's financial supervisors.
1. Is this a market crash, or a fraud case that spilled into the market?
Fundamentally the latter. The SPK's 17 September bulletin describes trades in Katılımevim and Gündoğdu Gıda shares as manipulative and imposes two-year trading bans and criminal referrals on Pusula Portföy chairman Muhammed Yarız and a number of fund managers. A separate referral targets İbrahim Bekçi, a manager at Tera's roughly 200-billion-lira TLY fund, over trading in Destek Finans Faktoring shares. Reporting in the Turkish financial press describes a mechanism in which shallow, illiquid stocks held inside closed fund structures were inflated and then floated publicly — a structure that came under strain once the SPK tightened rules following warnings from international index providers, including MSCI. Financial crimes police searched the headquarters of İnfo Yatırım, and Hedef Holding chairman Namık Kemal Gökalp was detained and his home searched; the precise charges against him have not yet been detailed by officials. International outlets reported that an arrest warrant was issued for Yarız as he reportedly left the country by private boat from Marmaris to Greece.
2. Why did trouble in a handful of funds take down the whole index?
Because the funds held the stocks, and redemption pressure forced them to sell. The banking index fell 5.4 percent on 16 September and industrials 5.1 percent — sector-blind selling that signals panic rather than a rotation out of a specific exposure. Two mechanical amplifiers made it worse: fund managers facing redemption requests had to liquidate positions into an already thin market, and the break below the 14,000-point support level triggered automatic stop-loss selling across brokerage accounts. The contagion then reached the would-be rescuer: shares in three Tera Group companies closed at the daily limit down, even as Tera insisted the transfer of Pusula's funds was not yet complete and that liability had not passed to it.
3. Who is actually exposed here, beyond equity traders?
Retail savers using a lightly regulated channel. Katılımevim, part of the Pusula group, fell from a peak of 69 lira to 27.46 lira — a loss of roughly 60 percent in thirteen days — and operates a savings-finance model through which more than 102,000 active members pay in over time to eventually qualify for home or vehicle financing. How much risk sits inside the pooled funds these companies manage is not publicly known, which is precisely what makes this episode politically sensitive: it is not hedge-fund money at risk, it is household savings accumulated toward a home purchase.
4. Were regulators warned, and did they act in time?
The warning came from the top of the finance ministry itself. Şimşek said as far back as last November that manipulation existed in both the exchange and the fund market; the events of this week show how far those risks had grown since that warning, despite tightened SPK rules in the interim. Borsa İstanbul had already imposed a temporary ban on short selling and margin trading in Katılımevim shares between 31 July and 28 August under its volatility-based precaution system — a sign supervisors were tracking the stock months before the default. The gap between that early flag and this week's criminal referrals and fund freezes is the story: surveillance existed, enforcement arrived only after investors had already been trapped.
5. What does this mean for Turkey's investment climate and the wider region?
Three things are worth watching from outside Turkey. First, credibility: the Financial Times framed this as a "fund run" with roughly a billion dollars withdrawn, and noted analysts see the underlying problem as broader than Pusula alone — this reads internationally as a governance failure, not a macroeconomic wobble, which is harder to resolve with liquidity alone. Second, the state's chosen instrument was administrative freezing rather than a backstop guarantee: halting trading in seven firms' funds protects the index number but leaves ordinary investors' cash locked up, a trade-off whose reputational cost will show up in foreign portfolio allocation decisions over the coming months. Third, timing is unhelpful — this crisis lands the same week the US Federal Reserve raised rates for the first time since 2023, tightening exactly the external financing conditions Ankara needs to stay loose as it manages the lira's gradual depreciation. Şimşek's disinflation programme has been built substantially on foreign investors trusting Turkey's market rules; this week tests that trust directly, not the underlying macroeconomic arithmetic.
What to watch next: Whether the SPK extends its measures to additional portfolio firms; how and when liquidation proceeds are returned to trapped fund investors; whether the Tera–Pusula acquisition survives regulatory review given the criminal exposure now attached to Pusula's management; and whether the central bank steps in with liquidity support if the trading freeze itself begins to generate secondary funding stress in the banking system.
Sources: Financial Stability Committee statement (17 September 2026); SPK bulletin 2026/60; T24, Cumhuriyet, Sabah, Bloomberg HT, TR724, Financial Times, IntelliNews reporting, 16–17 September 2026.