Trip.com Group shares cratered more than 20% in Hong Kong trading after China’s State Administration for Market Regulation announced an antitrust investigation. The watchdog alleges the travel giant engaged in monopolistic practices and abused its dominant market position. Shares hit an all-time low during the session, making it the worst performer on the local exchange and wiping out modest gains from the previous year.

The probe casts a shadow over Asia’s largest online travel agency just as the sector was showing signs of life. Chinese tourism had begun recovering through late 2025, fueled by government stimulus measures aimed at boosting domestic spending. Trip.com, which generates most of its revenue from Mainland China, had been positioned to benefit from that rebound.

Trip.com has pledged full cooperation with regulators, though the investigation’s scope and potential penalties remain unclear. The company operates extensive holdings beyond the mainland, but Beijing’s scrutiny reflects a broader pattern of tightening oversight on major tech firms. Investors now face uncertainty over how long the inquiry will last and whether it could force operational changes at the travel leader.

For context, China has ramped up competition enforcement in recent years, targeting sectors from e-commerce to ride-hailing. This action echoes past crackdowns that reshaped industry dynamics overnight. The key question moving forward is whether Trip.com can navigate these headwinds without losing momentum, or if this marks the start of a tougher regulatory era for the country’s online travel market.