By Bosphorus News Economy Desk
On November 2, 2026, Türkiye's widening investment fund investigation reached the leadership of two major capital market institutions, with former Borsa Istanbul chief Korkmaz Enes Ergun reported to have been referred to prosecutors and Takasbank General Manager Yunus Arıncı placed under judicial supervision. The inquiry involves investment funds, brokerage firms and billions of lira in disputed transactions.
Ergun, detained on October 31, was referred to the courthouse on Monday, Ekonomim reported. Prosecutors are investigating allegations of bribery and membership in an organization established to commit crimes. No subsequent judicial decision on his detention status had been independently confirmed by publication time.
Arıncı was questioned as a suspect and placed under judicial supervision, including a travel ban and regular reporting requirements. Turkish media reported that he had resigned, although a formal announcement from Takasbank was not available.
The developments follow weeks of regulatory intervention and criminal proceedings surrounding the suspension and liquidation of investment funds in September. Investigators have examined transactions involving portfolio companies, brokerage firms and individuals suspected of obtaining improper gains.
Leadership Changes at Borsa Istanbul and SPK
Borsa Istanbul appointed Deputy General Manager Atila Türeli as acting chief executive on November 1, following Ergun's detention.
Ergun had led the exchange since March 2021. The Istanbul Chief Public Prosecutor's Office announced his detention on October 31 but did not publicly identify the transactions underlying the allegations.
The Capital Markets Board of Türkiye (SPK) has also undergone a leadership change.
President Recep Tayyip Erdoğan appointed Muhsin Atcı, formerly head of the Tax Inspection Board, as SPK chairman through a decision published in the Official Gazette on November 1. Ersin Başar Ekmekci was named deputy chairman, while Yasemin Girici joined the board.
Atcı succeeds Mahmut Sütcü, who left the regulator in October. He takes over as the SPK manages fund liquidations, investor compensation and restrictions on market participants.
The appointments and administrative departures have not all been officially linked to the criminal investigation.
Takasbank's TL21 Billion Collateral and TL9 Billion Risk Figures
Arıncı's questioning has renewed attention to his October 14 appearance before parliament's Planning and Budget Committee.
During the hearing, he discussed Tera-related transactions in the Takasbank Money Market, citing approximately TL21 billion in collateral and a TL9 billion risk figure.
Arıncı subsequently described the TL9 billion figure as cumulative. The parliamentary explanation did not fully establish whether it represented outstanding exposure at a particular date or transactions accumulated over a period. It cannot be treated as a confirmed loss or missing funds.
He also addressed questions about Tera-linked funds admitted to the Turkish Electronic Fund Trading Platform (TEFAS), disclosures made through the Public Disclosure Platform (KAP) and the regulatory instructions governing those funds.
His testimony drew attention to how the exchange, its clearing infrastructure and the market regulator handled transactions during the period under investigation.
Takasbank and Borsa Istanbul have maintained that the clearing institution does not directly lend its own resources to brokerage firms through these arrangements. Instead, it operates a collateralized marketplace in which participants transact with one another.
No final judicial finding has established whether particular transactions breached market rules or whether individual executives bear criminal responsibility.
TL187.65 Billion in Gains Under Examination
Justice Minister Akın Gürlek said investigators had identified 214 individuals and companies associated with approximately TL187.65 billion in gains from funds linked to Tera, Pusula and Hedef.
The group includes 141 individuals and 73 legal entities.
Gürlek outlined approximately TL90 billion in gains associated with Tera, TL79 billion with Pusula and TL18 billion with Hedef. The figures represent findings reported by the authorities, rather than damages established by a final court ruling.
By October 30, 37 people had reportedly returned a combined TL18.34 billion.
That amount is equivalent to roughly 9.8 percent of the total gains under examination. Authorities have not published a complete accounting showing whether the repayments and the reported gains cover precisely the same transactions.
Money recovered during criminal proceedings is separate from investor compensation administered through fund liquidation.
As Bosphorus News reported in its examination of the compensation programme, regulators announced TL29.3 billion in advance payments covering 235,705 investors in seven funds. Full completion of the payments has not been publicly documented.
The original September intervention involved 131 funds managed by seven portfolio companies. Earlier regulatory figures identified 455,758 unique investors holding units in those funds.
Tera License Revoked, Separate Security Misses Coupon Payment
On October 27, the SPK revoked the operating authorizations and license of Tera Yatırım Menkul Değerler A.Ş., ordering investor compensation and the brokerage's gradual liquidation under Türkiye's Capital Markets Law.
The decision was disclosed through KAP on October 30.
A separate payment problem emerged that day when an asset-backed security issued through Türkiye Menkul Kıymetleştirme Şirketi's Tera Bank Second Asset Finance Fund failed to make a scheduled coupon payment.
The security, identified by ISIN TRPTMT212733, was transferred to Borsa Istanbul's Debt Securities Watchlist Market. Trading was suspended for November 2, with reopening scheduled for November 3.
A disclosure by Birleşik İpotek Finansmanı A.Ş. attributed the missed payment to cash held at Tera Yatırım Bankası A.Ş. that the bank had been unable to transfer to Takasbank.
The unpaid coupon amounted to TL146.94 million.
Tera Yatırım Menkul Değerler, Tera Yatırım Bankası and the asset finance fund are separate legal entities. The disclosures identify a payment failure involving the bank but do not establish that the brokerage's license cancellation caused it.
Eximbank Chairman Osman Çelik Leaves
Another senior departure in Türkiye's financial sector was confirmed on November 2, when Türk Eximbank disclosed through KAP that Osman Çelik had left both its board chairmanship and board membership.
The notification, published at 15:21 local time, gave no reason for his departure.
Çelik previously served as deputy treasury and finance minister and had reportedly sought retirement from that position in October. His departure from Eximbank has attracted attention amid the fund investigation, but no official record identifies him as a suspect or directly connects the decision to the proceedings.
Market Losses and Outstanding Investor Claims
The investigation comes amid a prolonged decline in Turkish equities.
The BIST 100 fell from approximately 14,467 points on September 11 to 10,759.56 on October 30, a decline of about 25.6 percent over seven weeks.
Opposition politicians have also pointed to a much larger reduction in the aggregate market capitalization of listed companies.
According to figures presented by DEVA Party leader Ali Babacan and reported by Karar, the combined market capitalization of listed companies fell by approximately $173.5 billion between the end of August and the end of October.
That decline cannot be treated as a verified estimate of losses caused by the suspected fund transactions. Market capitalization reflects changes in share prices across listed companies and differs from cash losses realized by investors.
Bosphorus News previously examined concerns over concentrated holdings and pricing distortions in low-float Turkish shares, including warnings raised by MSCI before the September intervention.
Investors are still awaiting a full accounting of how much money can be recovered, what compensation has been paid and which claims remain against the funds and financial institutions involved.
Prosecutors must determine whether the evidence gathered supports further charges, while the SPK continues overseeing liquidation and compensation procedures.
Further disclosures are also needed on the missed Tera Bank-linked coupon payment. No final judicial determination of criminal responsibility has been announced.
Sources: Istanbul Chief Public Prosecutor's Office statements; Borsa Istanbul; Capital Markets Board of Türkiye; Public Disclosure Platform (KAP), notifications 1689657, 1689686, 1690145 and 1690881; Turkish Grand National Assembly committee proceedings; Anadolu Agency; Reuters; Bloomberg HT; Ekonomim; Karar; Bosphorus News reporting and document review.