Chinese spies stole trade secrets from Dutch chip machine maker ASML, causing hundreds of millions of euros worth of damage, Financieele Dagblad reports based on its own research. This is the largest known espionage case ever at a Dutch company, the newspaper writes.

The secrets were stolen by highly-placed Research and Development employees at the company, who had indirect ties to the Chinese government, according to FD. As ASML employees, they had access to the internal networks of the ASML establishment in San Jose in the United States for years. They stole source code, software and pricing strategies and passed the information on to XTAL - a competitor of ASML that was established in 2014.

XTAL receives state aid from China, with the aim of strengthening the Chinese position on the chip market. ASML is currently the world leader on that market, according to FD. With the stolen knowledge, XTAL managed to hijack clients like electronics giant Samsung from ASML. A court in California already fined the company 223 million dollars for that.

ASML is expected to respond later today.

D66 parliamentarian Sjoerd Sjoerdsma pointed out that intelligence service AIVD has been warning about Chinese espionage for years. "And rightly so it again appears", he said on Twitter. "We as EU will have to act harder in the WTO to do something about this."