A court in Beijing has agreed to hear an unfair competition lawsuit launched by e-commerce firm JD.com against Tmall.com.
JD.com is accusing Tmall of exaggeration on some of its outdoor and newspaper ads in September that promised same-day delivery in Beijing.
JD.com says only people living in certain parts of the city are eligible to get the service, and only on items ordered before a certain time of the day.
The company notes many people still have to wait until the next day to get their packages.
JD.com is demanding Tmall stop posting the ads and release a statement admitting they had been deceptive.
Alibaba, which owns Tmall, has yet to comment on the suit.
The lawsuit comes after the State Administration for Industry and Commerce formally accepted JD.com's request to investigate Alibaba for possible unfair promotional practices.
JD.com claims Alibaba is "forcing merchants" to choose to deal exclusively with one e-commerce site for their promotional activities.
Alibaba has denied the accusations.
