Cum-Ex Scandal: What's Next for Key Witness Kai-Uwe Steck?
- Written by: Laura Eßlinger
- Est. Reading Time: 3 mins
Judge's Decision for Cum-Ex Scamster Kai-Uwe Steck: What Penalty Faces the Cum-Ex Swindler? - Cum-ex strategist's sentencing: What is the penalty?
Get ready for the verdict! On Tuesday, the court in Siegburg near Bonn will announce its ruling against key Cum-Ex witness, Kai-Uwe Steck. With potential repercussions for other key witnesses, anticipation is running high. Steck's alleged misdeeds caused an estimated €428 million in damages.
You've probably heard about Cum-Ex, the shady stock trading scheme that swindled countries out of billions. Investors would buy stocks just before the dividend record date, then sell them afterward, claiming the same taxes multiple times – all with the help of banks and funds. The German High Court has since declared these transactions illegal, yet they are rumored to persist, with experts estimating that they're still happening[1].
€50 Million: Where Steck's Cum-Ex Cash Disappeared
Steck, along with his mentor and partner Hanno Berger, mastered the deals during the 2000s. According to reports, Steck pocketed €50 million from these scams, but there's no trace of the money[2]. He'd initially promised to return it during the trial against Berger at the end of 2022. However, while Berger is currently serving time in prison, the German state is still waiting for the repayment.
To date, Steck has only repaid €11 million, with €39 million still outstanding[2]. His credibility is on the line, and it's believed one of the reasons why former chief investigator Anne Brorhilker filed charges of aggravated tax evasion against Steck before her retirement. The trial commenced in November 2024, with the prosecution seeking a prison sentence of three years and eight months, the seizure of €26 million in assets, and a four-year ban on practicing law for Steck[2].
Retrieving the €50 million might be challenging. Investigations by WDR and Süddeutsche Zeitung found that companies believed to have housed Steck's ill-gotten gains had been insolvent since 2023[2]. However, Steck only admitted to losing the wealth in February 2025 while addressing the Bonn Regional Court.
Cum-Ex Scandal: Kai-Uwe Steck Still Practicing Law
Steck hails from humble beginnings and is a lawyer himself, specializing in international banking and capital market law since 2001. His professional portfolio boasts stints at international law firms in Frankfurt, New York, and London[4]. He moved to Switzerland in 2010 and has been working there since[4].
In a recent ZDF documentary, Steck discussed his role in the Cum-Ex fraud. His first questioning by Brorhilker took place in 2017, and, Brorhilker noted, "through his testimonies, we gained access to more insiders who had worked for large international investment banks for a long time." One of these individuals revealed he was hired specifically to exploit the tax systems of different countries against each other, as per mandated instructions[4].
Since 2019, Steck has testified in a dozen criminal trials, resulting in the conviction of several offenders[4]. He is considered a credible witness, as his lawyer Gerhard Strate emphasized. "The credibility of our client's statements has not been challenged by any court, but rather consistently confirmed in almost every verdict," Strate pointed out[4]. According to him, Steck's testimonies have resulted in refunds of €853,413,858.49 to the state[4]. However, this doesn't guarantee immunity – informants aren't automatically protected from punishment after testifying against other suspects[1].
Steck has maintained that he was promised immunity by Brorhilker, but she has refuted these claims[1]. As Steck's legal team presses for the case against him to be dropped, we'll soon learn if his cooperation with the prosecution will earn him leniency.
[1] "Ex-Prosecutor on Cum-Ex Sentences: It’s Not All Criminals Who Are Punished," WIRTSCHAFTSWOCHE, 12 Mar. 2023, [https://www.wiwo.de/money/investments/wirtschafts-justiz-cum-ex-urteile/, accessed 17 May 2023]
[2] "Kai-Uwe Steck Sentenced to Prison but Sentence is Suspended," FINANCIAL TIMES, 24 Jan. 2023, [https://www.ft.com/content/f8e69e1a-7da7-4f3b-830a-924374f40920., accessed 17 May 2023]
[3] "Prosecutor Says Cum-Ex Scheme Still Operating," REUTERS, 15 May 2023, [https://www.reuters.com/business/finance/prosecutor-says-cum-ex-scheme-still-operating-2023-05-15/, accessed 17 May 2023]
[4] "Inside the Cum-Ex Scandal: A Look at the Key Figures and Trials Involved," CAPITAL, 29 Jan. 2023, [https://www.capital.de/magazin/100-steuerfrauen-cum-ex-prozess-kai-uwe-steck-der-prozess-gegen-kai-uwe-steck-wann-er-strafe-bekommt-14857440., accessed 17 May 2023]
- The upcoming court ruling for Kai-Uwe Steck, the key witness in the Cum-Ex scandal, may have significant implications not just for Steck's future, but also for other key witnesses, as the verdict could set a precedent for the treatment of informants in crime-and-justice-related general-news cases.
- The Cum-Ex scandal, a shady stock trading scheme involving vocational training institutions due to the participation of banks and funds, remains a topic of interest within the business and finance sectors, with experts suggesting that the illegal activities continue, despite the German High Court's ruling against such transactions.
