Shares of Blackstone surged 14.4% to $143.55 in after-hours trading on September 10, reversing a week-long slide from $137.68, after the world's largest alternative asset manager announced a deal to buy Flow Control Holdings, a Cincinnati-based maker of specialized cooling parts for AI data centers. Financial terms were not disclosed, and the transaction is expected to close in the fourth quarter. The move signals Blackstone is deepening an already massive AI infrastructure play — but the size of the stock reaction raises questions about how much hype the market is pricing in.
• The Deal Plugs Blackstone Into the Plumbing of the AI Boom. Blackstone's private equity funds, spanning both its Capital Partners and Energy Transition Partners arms, will acquire Flow Control Holdings from Audax Private Equity.
The target makes precision components used by major cloud providers and equipment manufacturers for systems that pipe liquid coolant directly to overheating AI chips.
Blackstone described AI infrastructure buildout as "one of Blackstone's highest-conviction investment themes" and pledged to invest in capacity expansion. Under Audax, FCH completed 10 acquisitions and expanded production and distribution capacity — a buy-and-build playbook Blackstone now inherits.
• Liquid Cooling Is a Fast-Growing Market — and Blackstone Is Stacking Bets Around It. The global data center liquid cooling market was valued at roughly $4.8 billion in 2025 and is projected to expand to $27 billion by 2035, growing at about 18% annually. That growth exists because AI chips generate far more heat than traditional servers, and air cooling alone can't handle it. Blackstone is already investing $5 billion in a Google joint venture targeting 500 MW of data center capacity by 2027 , and it filed in April for an IPO of a new data center REIT, Blackstone Digital Infrastructure Trust. Flow Control adds a component-level grip on the supply chain feeding all of these facilities.
• A 14% Jump on an Undisclosed-Price Deal Deserves Scrutiny. BX shares had fallen roughly 9% over the prior five sessions amid hotter-than-expected producer inflation. The after-hours spike erased all of that and then some — yet no purchase price, revenue, or margin data has been released. Without knowing what Blackstone paid, investors are essentially cheering a narrative, not a number. Audax retains a minority stake , suggesting the seller sees further upside, but also that Blackstone didn't demand full control.
• The Bigger Picture: Blackstone Is Becoming an AI-Infrastructure Conglomerate. Blackstone acquired QTS Data Centers for $10 billion in 2021 , and QTS has since expanded leased capacity by 14 times. Adding cooling components, a REIT shell, and a hyperscaler partnership means Blackstone now touches nearly every layer of the data center stack. The strategic logic is sound; the question is whether the stock already reflects it.