Amazon has disrupted fashion, books, furniture, food, cloud-based storage services, and much else besides. Now, it’s coming for one of the biggest, most complex industries in the US: healthcare.

Today (Jan. 30), Amazon, Berkshire Hathaway, and JPMorgan announced a vague but market-moving plan to launch an independent company that will offer healthcare services to the companies’ employees at a lower cost. The venture, which will be managed by executives from the firms, will be run more like a non-profit, than a for-profit entity.

The market value of 10 large, listed health insurance and pharmacy stocks 1 dropped by a combined $30 billion in the first two hours of trading. At the time of writing, insurer MetLife was the hardest hit, down nearly 9% for the day.

“The healthcare system is complex, and we enter into this challenge open-eyed about the degree of difficulty,” said Amazon’s Jeff Bezos in a statement. “Hard as it might be, reducing healthcare’s burden on the economy while improving outcomes for employees and their families would be worth the effort. Success is going to require talented experts, a beginner’s mind, and a long-term orientation.”

“The healthcare system is complex, and we enter into this challenge open-eyed about the degree of difficulty,” said Amazon’s Jeff Bezos in a statement. “Hard as it might be, reducing healthcare’s burden on the economy while improving outcomes for employees and their families would be worth the effort. Success is going to require talented experts, a beginner’s mind, and a long-term orientation.”