UBS on Friday criticised EU antitrust regulators over the way they calculated its 172.4-million-euro ($186 million) cartel fine, saying the arbitrary figure was based on inaccurate assumptions that resulted in a big penalty.
The Swiss bank was penalised by the European Commission in 2021 for taking part in a European government bond trading cartel between 2007 and 2011, in the midst of the European debt crisis. Its fine was the biggest.
The financial industry has been fined billions of euros worldwide in recent years for rigging foreign exchange, Euribor and Libor benchmarks and bonds.
UBS subsequently challenged the EU decision at the General Court, Europe's second-highest.
While the bank estimated the relevant value of sales used to calculate the fine should be 89 million euros, the EU competition enforcer used its own figure of almost 300 million euros, UBS lawyer Christian Riis-Madsen told judges at a hearing.
"Because of this new methodology, the fine imposed on UBS was several times larger than it should have been," he said.
"What is dressed up as a scientific calculation in reality is a series of stack proxies and assumptions," Riis-Madsen said. "The overall approach leads to an arbitrary outcome and must be rejected."
Commission lawyer Thomas Franchoo rejected the criticism.
"The fine needs to reflect the economic importance of the infringement, and the relative contribution of each of the participating undertakings to that infringement," he told the court.
Other penalised banks were UniCredit and Nomura . NatWest dodged a fine as it alerted the cartel to the EU antitrust watchdog.
Bank of America and Natixis were also not fined because their infringement fell outside the limitation period while Portigon, the successor to WestLB, received a zero fine as it did not generate any net turnover in the last business year.
The court will rule in the coming months.