Amazon is taking a $3.9 billion step toward expanding its primary care options this morning with the acquisition of One Medical.

One Medical is a publicly traded, membership-based primary care practice offering virtual and brick-and-mortar services to commercially insured patients.

The deal was announced before the stock market opened. One Medical, which closed at $10.18 per share yesterday, is trading nearly 70% higher as of press time. 

Under terms of the all-cash deal, Amazon will pay $18 a share for One Medical. Amir Dan Rubin, One Medical’s CEO, will stay on once the deal is approved by One Medical’s shareholders and federal regulators.

Amazon has been persistent in its healthcare push even after the company’s joint healthcare-specific venture with J.P. Morgan Chase and Berkshire Hathaway disbanded last year. In February of this year, the company said it was expanding its virtual primary care and urgent care service, Care Medical, nationally into 20 new cities. 

Late last year, Amazon launched a central arm to consolidate its various healthcare business efforts, tapping a former senior vice president of its Amazon Prime business, Neil Lindsay, to lead it.

“We think health care is high on the list of experiences that need reinvention,” Lindsay said in a statement. “We want to be one of the companies that helps dramatically improve the healthcare experience over the next several years.