HONG KONG (Reuters) -U.S. investment firm Bain Capital is seeking to sell the China business of data centre operator WinTriX DC Group, in a deal that could value the business at over $4 billion, two people with knowledge of the situation said.

Bain Capital has engaged with advisers who have held preliminary conversations with potential buyers in recent months, said the people, declining to be named as the information was not public.

The China business of WinTriX, formerly known as Chindata Group Holdings, has estimated 2025 earnings before interest, taxes, depreciation, and amortisation (EBITDA) of close to 4 billion yuan, they said.

Bain Capital declined to comment. The data centre operator did not respond to a Reuters request for comment.

The potential deal comes nearly two years after Bain Capital took Nasdaq-listed Chindata private in a $3.16 billion deal.

Bain Capital first acquired Chinese data centre operator Chindata in 2019 and merged it with Southeast Asia data centre operator Bridge Data Centres in the same year. The listed entity was a combination of both.

Since the take-private, the Boston-based firm separated the two businesses again under WinTriX, said a third person with knowledge of the situation.

The sale also comes as data centre valuations have soared in the last few years, driven by rapid developments of artificial intelligence.

Last year Australian data centre operator AirTrunk was sold to a Blackstone-led consortium for over 20 times its forward core earnings, Reuters reported.

WinTriX's Chinese rival GDS Holdings is currently trading at a price-to-earnings multiple of 8.48 times, LSEG data showed.

Fitch Ratings however in February downgraded WinTriX's long-term foreign- and local-currency issuer default ratings to "BB" from "BBB" with a stable outlook, which it said reflected its expectations that WinTriX would face significantly higher business risks as it changed its strategy to focus on overseas investment.

Fitch cited slower hyperscale data centre demand and higher competition in China as one of the additional risks WinTriX would face.

WinTriX counts social media giant Bytedance as its largest customer, which contributed to 86% of its revenue in 2022, according to the Fitch report.

Outside China, it also operates data centres in India and Malaysia.

In March, WinTriX's unit Bridge Data Centres, which operates data centres outside China, secured a $2.8 billion bank financing to fuel its data centre expansion, it said at the time.

Bain Capital will keep its control of Bridge Data Centres for the time being, said the sources.