It's riskier than ever to be a foreign business in China, as evidenced by a series of recent sanctions, detentions, and an updated anti-espionage law that has watchdogs on edge

• Beijing recently passed wide-ranging updates to its anti-espionage laws, worrying foreign investors.
• The updated law doesn't clearly define what constitutes China's national security or interests.
• The new law follows a recent spate of sanctions, probes, and detentions into foreign firms in China.

Foreign businesses in China have faced numerous challenges like intellectual property protection and geopolitical tensions with the US — but now, operating in the country could get trickier.