HONG KONG — After a customer canceled a large order at the last minute, shares in Aixtron, a German high-tech company, sank fast. Months later, with the stock still reeling, a Chinese investor agreed to buy the company.

If only it were as simple as smart deal-making.

Financial filings and public statements indicate a web of relationships among the customer, the buyer and the Chinese state. The links highlight the blurred lines between increasingly acquisitive Chinese companies and Beijing’s long-term industrial policy.

“The Aixtron case makes it very clear: It is not regular investment that is at work here,” said Sebastian Heilmann, president of the Mercator Institute for China Studies, a think tank based in Berlin. “Instead, we see governmental-program capital working behind the scenes.”

Chinese leaders have made clear their intention of using state funds to acquire technological capabilities overseas and bring them home, and a series of purchases in recent years have highlighted that strategy.