The long-running criminal case against shipbuilder Damen Shipyards opened on Monday, with the company facing allegations of large-scale bribery and breaching sanctions against Russia.

The hearings, held in Zwolle, are preliminary and focus on the structure and planning of a trial that is expected to take years.

Damen, based in Gorinchem and with annual revenues of €3 billion, is the Netherlands’ largest shipbuilder and the country’s only marine yard capable of producing naval vessels.

Alongside the company itself, president-commissioner Kommer Damen, current chief executive Arnout Damen and former chief executive René Berkvens are all under investigation. The accusations include years of bribery, falsifying documents and, in a separate case, exporting ship components to Russia in violation of EU sanctions.

Many of the alleged offences are said to have ended shortly after a major raid by the FIOD tax investigation service at Damen’s headquarters in January 2017.

The corruption case alone has taken the public prosecution service eight years to investigate, and the defence is expected to call more than 100 witnesses, including several from countries such as Sierra Leone, Curaçao and Barbados.

The charge sheet reportedly runs to 89 pages and includes alleged covert payments to officials at Brazilian oil group Petrobras and the port authority on Curaçao, as well as undisclosed commission arrangements in Sierra Leone, Togo, Ghana, the Bahamas, Trinidad and Tobago and Indonesia.

Prosecutors also claim that Damen used incorrect export codes in 2022 to conceal that ship hulls sent by it to Russia fell under sanctions. It is the first time a major European defence contractor has faced prosecution for sanctions-busting.

Monday’s hearing also features British intermediary Stephen Hobson, now 77, who earned tens of millions of euros in commissions on Damen contracts in the Caribbean, according to the Financieele Dagblad.

Hobson is no longer accused of bribery, but still faces charges of falsifying documents by recording commission rates that prosecutors say were unrealistically low.

He rejects the accusations and will ask the court to separate his case from the wider Damen proceedings, arguing that his age and health make it unlikely he would live to see the end of a lengthy joint trial.

Damen said in a statement that it approaches the proceedings “with full confidence” and welcomes the opportunity to explain why it believes the suspicions are unfounded.

If Damen Shipyards Gorinchem and Damen Schelde Naval Shipbuilding are convicted, they face exclusion from public contracts and fines of up to 10% of annual turnover. The executives themselves could face prison terms.