Zypries said that while Chinese takeovers in Europe bring capital inflows that "prove the attractiveness of European locations and help safeguard jobs across the bloc including Germany", she thinks it is clear that China is looking to buy access to European technology while protecting its own companies from European investors.
In Germany alone there was more Chinese investment in 2016 than over the previous 10 years and 2017 looks ready to surpass that again, she said.
The influx of capital can be positive, Zypries said. Foreign direct investment is a driver for growth, value creation and job creation.
But on the other hand, it has been clear for some time that China is concentrating on high-tech industrial technology companies, Zypries said.
At the same time, many areas of the Chinese market remain closed to European investors, she said, and "open markets cannot be a one-way street".
EU states must be able to impose conditions on, or even prohibit, state-controlled or subsidised acquisitions of companies who are developing or manufacturing important technologies, Zypries said.
Zypries' letter follows a policy paper prepared by Germany, France and Italy in July calling for the Commission to protect Europe's most innovative companies. The paper proposed that the Commission should determine whether acquisitions are based on a foreign country’s political objectives rather than market forces, and called for reciprocity of investment conditions.