Oracle announced a deal to acquire the electronic health-records company Cerner for $95 a share in cash, or $28.3 billion. Reports that talks between the two companies were under way surfaced last week .

Oracle (ticker: ORCL) said the transaction, which will be the biggest it has made to date by far, will be accretive to earnings on a non-GAAP basis in the first full fiscal year after closing. It "will contribute substantially more to earnings in the second fiscal year and thereafter," the company said.

The deal is expected to close in calendar 2022, subject to regulatory approvals and other closing conditions, including a majority of Cerner (CERN) holders accepting the offer.

Oracle said it expects to retain an investment-grade credit rating after completion of the acquisition. While it seems clear that Oracle will need to finance at least part of the transaction, the company didn't immediately provide any details on how it might do so. As of the end of November, Oracle had about $22.8 billion in cash and securities, offset by about $73.4 billion in long-term debt, leaving them with $50.6 billion in net debt.

The company said it plans to maintain and expand Cerner's presence in its home base in Kansas City, Mo.

"Working together, Cerner and Oracle have the capacity to transform healthcare delivery by providing medical professionals with better information – enabling them to make better treatment decisions resulting in better patient outcomes," Oracle Chairman Larry Ellison said in a statement.

"With this acquisition, Oracle's corporate mission expands to assume the responsibility to provide our overworked medical professionals with a new generation of easier-to-use digital tools that enable access to information via a hands-free voice interface to secure cloud applications. This new generation of medical information systems promises to lower the administrative workload burdening our medical professionals, improve patient privacy and outcomes, and lower overall healthcare costs."

Cerner CEO David Feinberg added in a statement that "joining Oracle as a dedicated Industry Business Unit provides an unprecedented opportunity to accelerate our work modernizing electronic health records, improving the caregiver experience, and enabling more connected, high-quality and efficient patient care."

It is worth noting that Oracle has been considering a bid for a long time. Cerner's name was on an internal list of nine potential acquisition targets that surfaced in 2004 in connection with litigation tied to the company's acquisition of PeopleSoft. (Every other company on that list has now been acquired by Oracle, SAP, or some other company.)

While Oracle has a long history of making acquisitions, this outranks any of the previous deals in terms of size. Oracle paid $9.3 billion for NetSuite in 2016, $7.4 billion for Sun Microsystems in 2010, $8.5 billion for BEA Systems in 2008, $5.9 billion for Siebel Systems in 2006, and $10.3 billion for PeopleSoft in 2005.

The deal prices Cerner at a little under five times current Wall Street estimates of $6.1 billion in 2022 sales. Stifel analyst Brad Reback pointed out in a research note last week that Cerner has a gross margin in the low 80% range but operating margins of just 20%, "leaving a significant amount" of operational efficiency to capture."

In Monday trading, Oracle shares were down 2.4% to $94.26, while Cerner shares are up 1% to $90.71.