SYDNEY (Reuters) - A criminal cartel case against Australia and New Zealand Banking Group ANZ.AX and the local units of Citigroup C.N and Deutsche Bank DBKGn.DE was adjourned on Tuesday for further legal arguments ahead of a possible trial.

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Australian authorities filed charges last year against the firms and six senior bankers over the sale of A$3 billion ($2.1 billion) in ANZ shares in 2015 and subsequent trading by the underwriters.

The case is being closely followed by brokers and banks around the globe because it could have major implications for the underwriting business and lead to increased scrutiny from regulators worldwide.

It was standing room only as lawyers crammed into a tiny courtroom in Sydney for the brief procedural hearing, setting dates in September when lawyers for the banks and bankers will press to be allowed to cross-examine prosecution witnesses.

“We’re going to need a bigger courtroom,” Magistrate Jennifer Atkinson said, before fixing the case for its next mention on Sept. 3 and two days of arguments on Sept. 25 and 27.

None of the accused executives were present and it is not clear if or when the matter will proceed to trial. Prosecution lawyer Shanaka Jayasuriya said in court that he would oppose his witnesses being cross examined, without elaborating.

The government accuses the banks of forming a criminal cartel to either “directly or indirectly” restrict the supply of ANZ shares or maintain the price of ANZ shares, according to court documents.

The banks and bankers are all defending the charges. ANZ did not immediately respond to a Reuters request for comment on Tuesday. Citigroup had no commend but has previously said it had “operated successfully in Australia in this manner for decades”.

Deutsche referred to a previous statement saying it will vigorously defend the charges and its staff.

JPMorgan JPM.N, which underwrote the capital raising along with Citigroup and Deutsche Bank, has not been charged. A representative declined to comment.

If convicted, the companies could face penalties of up to A$10 million or triple the benefit of the conduct. The individuals charged could face 10 years in jail.

ANZ, Australia’s third-largest bank, is also facing civil charges over the same share issue by the country’s corporate watchdog, though that case was paused in June pending the outcome of the criminal matter.