Hewlett-Packard, which has spent the past year downplaying what had once been an aggressive push into the business of providing a “public cloud,” is exiting that business altogether.

The company will “sunset” its product, HP Helion Public Cloud, on Jan. 31, 2016, according to a new blog post by Bill Hilf, senior vice president of HP Cloud.

Public clouds are one form of “cloud computing,” in which tasks are performed over a network of distributed computing resources, rather than “locally” in the customer’s own data center. In a “public” cloud, those resources are shared by the public; in “private” clouds, the resources are used exclusively by one organization.

As many suspected, HP HPQ will foster interoperability with the biggest of the big public clouds: Amazon Web Services AMZN and Microsoft Azure MSFT . Just over a year ago, HP bought Eucalyptus, which offered private cloud technology that interoperated with AWS. And HP has had a long—and sometimes complicated—relationship with Microsoft. Hilf himself came to HP from the Redmond, Wash.-based software company.

HP’s decision is the latest milestone in what has been a slow fade for the company’s public cloud ambitions. It has become increasingly clear that there are three, maybe four companies that can support (at scale) the massive shared computing, networking, and storage infrastructure necessary for a public cloud. Those companies are Amazon, Microsoft, and Google GOOG .

HP will continue pushing its private and hybrid cloud. “To support this new model, we will continue to aggressively grow our partner ecosystem and integrate different public cloud environments,” Hilf wrote. “To enable this flexibility, we are helping customers build cloud-portable applications based on HP Helion OpenStack and the HP Helion Development Platform.”

He added: “For customers who want access to existing large-scale public cloud providers, we have already added greater support for Amazon Web Services as part of our hybrid delivery with HP Helion Eucalyptus, and we have worked with Microsoft to support Office 365 and Azure. We also support our PaaS customers wherever they want to run our Cloud Foundry platform – in their own private clouds, in our managed cloud, or in a large-scale public cloud such as AWS or Azure.”

PaaS stands for “platform as a service,” industry shorthand for a turnkey suite of cloud computing services that allow companies to quickly launch business applications.

On a macro level, HP’s decision is part of a massive shake up in the information technology business in which former superpowers—IBM IBM , EMC EMC , HP, and Cisco CSCO —find themselves facing an existential threat as their customers increasingly take their computing jobs to the pooled data center capacity that is the public cloud.

And, insult to injury, many of the major public cloud players run commodity hardware made to their specifications by no-name hardware makers—not IBM, EMC, HP, or Cisco—making the transition even more difficult for the old guard. It’s a threat that helped drive Dell’s $67 billion bid to buy EMC and has informed HP’s move to split into two companies: one focused on the enterprise, and one focused on PCs and printers.

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