Microsoft, on an accelerated growth push, is buying speech recognition company Nuance in a deal worth about $16 billion.

Microsoft will pay $56.00 per share cash. That’s a 23% premium to Nuance’s Friday closing price. The companies value the transaction at $19.7 billion, including debt.

Shares of Burlington, Mass.-based Nuance surged about 19% in today’s premarket trading.

Microsoft’s acquisition of Nuance comes after the companies formed a partnership in 2019. The Redmond, Washington, company said that the deal will double its total addressable market in the health care provider industry, bringing its total addressable market in health care to nearly $500 billion.

Nuance’s products include the Dragon Ambient eXperience, Dragon Medical One and PowerScribe One for radiology reporting, all clinical speech recognition SaaS offerings built on Microsoft Azure.

“AI is technology’s most important priority, and healthcare is its most urgent application,” Microsoft CEO Satya Nadella said in a statement.

The transaction is Microsoft’s second largest deal following its $26 billion purchase of LinkedIn in 2016. Last September, it bought video game maker ZeniMax for $7.5 billion.

“This is the right acquisition at the right time with Microsoft doubling down on its health care initiatives over the coming years,” Wedbush analyst Daniel Ives wrote in a note to clients.

Ives said the transaction fits well into Microsoft’s health care portfolio and comes at a time that hospitals and doctors are embracing next generation AI capabilities.

Mark Benjamin will continue as Nuance CEO.

The transaction is expected to close this year. It needs approval from Nuance shareholders.