What happened

Shares of JD.com (JD 5.80%) fell 11% on Tuesday as investors grew increasingly concerned that the Chinese e-commerce leader would soon embark on a potentially costly strategy to win back market share from its rivals.

So what

Now that the Chinese government has eased its COVID-related restrictions and reopened its economy, the country's online retail giants are reportedly gearing up for an intense battle for e-commerce supremacy, according to Bloomberg.

Investors are worried that intensifying competition will hurt JD.com's profits. The company is reportedly planning to implement a roughly $1.5 billion subsidy campaign to improve its prices and strengthen its standing as a low-cost e-commerce platform. Although the purported subsidies would likely boost JD.com's sales, they could also dent its profit margins.

The news stoked fears of a pending price war between JD.com and its rivals Alibaba and Pinduoduo. It also sparked concerns that JD.com's heavy investments in its massive fulfillment network might not be producing the desired effect of winning business from low-priced retailers.

Now what

JD.com is stuck between a rock and a hard place. If it lowers prices, its profitability will likely suffer, at least in the near term. But if it doesn't, it risks ceding ground to more aggressive competitors.

Investors don't seem to like either of those two options. They also don't like when a company's margins contract. And even the hint of a price war can send them running for the exits. Many of JD.com's shareholders decided to do just that and sell their shares today.