Firms including JPMorgan Chase & Co., Citigroup Inc., Bank of America Corp. and Barclays Plc have been frozen out of syndicating bond sales for the European Commission’s roughly 800 billion-euro ($970 billion) NextGenerationEU program, which is expected to issue 80 billion euros of debt this year. The banks have been temporarily barred from the lucrative trades as the bloc assesses whether they’ve done enough to fix previous breaches of antitrust rules.

The move has the potential to reshape debt league tables for the region, hand hefty fees to smaller competitors and even weigh on bankers’ bonuses. Tuesday’s 20-billion euro issuance by the bloc — the largest amount the EU has raised in a single transaction — may have generated more than $20 million in fees, according to estimates by Bloomberg.

Syndications are a “cash cow,” said Liam O’Donnell, head of nominal rates at Aberdeen Standard Investments. It “certainly would have been a profitable environment recently with multiple syndications.”

The banks affected are a Who’s Who of global banking with Deutsche Bank AG, Nomura Holdings Inc., UniCredit SpA, NatWest Group Plc, Natixis SA and Credit Agricole SA also barred. Spokespeople for the 10 banks declined or didn’t respond to requests for comment. IFR reported the news earlier.

“These banks have to demonstrate and to prove that they have taken all the necessary remedial actions which have been demanded by the Commission when deciding about these cases,” budget commissioner Johannes Hahn told reporters Tuesday. “We now expect the submission of the necessary information and then of course we have to analyze and assess it. I cannot predict how long it takes.”

While the exclusion is unlikely to make or break the trading year for most desks, the scale of the missed fees could snowball. Another two syndications are due before the end of July.

The EU’s big-ticket transactions account for a large part of banks’ business in the European market for new bond issues this year. The amount of EU bonds that dealer banks have sold this year typically amounts to more than 10% of their transactions in other European bonds, based on data compiled by Bloomberg.

This makes it hard to effectively replace the EU as a source of fee revenue in Europe. Even though other issuers may offer a higher fee than the EU’s 0.1% for this maturity, they are nowhere near as prolific in terms of issuance volume.

Primary Dealers

The 10 banks barred from the syndications are among a list of 39 so-called “primary dealers,” which have a responsibility to bid for bonds during regular debt auctions. The EU is expected to begin those in September.

Stopping banks from participating in bond sales is rare, and a first for the EU since it started selling debt in meaningful sizes under its social program last year. Morgan Stanley temporarily lost its status as a primary dealer of French government bonds in August as a result of transactions that took place in 2015.

In April this year, Bank of America was among banks fined about 28.5 million euros by European Union regulators for colluding in chatrooms on trading of U.S. supra-sovereign, sovereign and agency bonds. And in May, Nomura and UniCredit were among those fined for colluding on euro government bond trading during the region’s sovereign debt crisis.

Investor Demand

The missing banks didn’t seem to dent demand Tuesday with around 142 billion euros of investor orders for the offering. The lead managers for Tuesday’s sale were BNP Paribas SA, DZ Bank AG, HSBC Holdings Plc, IMI-Intesa Sanpaolo SpA and Morgan Stanley, with Danske Bank A/S and Banco Santander SA hired as co-leads.

Despite its hardline stance, the EU offered some hope of a swift resolution to the banks it has excluded — assuming they satisfy its requirements.

It is in the EU’s “interest to include all the key players and banks which have qualified themselves for the primary dealer network,” Hahn, the commissioner, said. “But of course the legal aspects have to be respected.”

–With assistance from Tommaso Ebhardt, Donal Griffin, Alexandre Rajbhandari and Hannah Benjamin.