China's government has never shown much concern for the privacy of citizens. If you have something to hide, the thinking goes, we probably need to know it. In one form or another, surveillance and monitoring have evolved into a well-honed form of social control. And as a result, neither companies nor consumers have traditionally had very high expectations for individual privacy.

That might've been fine before more than 700 million Chinese went online, and before the government began counting on sectors such as e-commerce to ease the economy's dependency on investment and exports. If China's biggest online players want to chart a bigger role for themselves at home and abroad, they're going to need to start taking privacy much more seriously.

The problem came into sharp focus this month, with new data showing that Chinese police had arrested 4,261 suspects in 1,886 cases related to the theft of personal information last year. That's a steep increase from prior years. Between 2010 and 2014, there were roughly 260 prosecutions under China's law prohibiting the sale of personal information. Last year's suspects included nearly 400 "industry insiders" in banking, e-commerce, telecommunications and delivery services. One estimate placed losses related to these reported crimes at $13.2 billion. Almost certainly, the scale of the problem is much bigger.