The Trump administration has promoted short-term health plans as less-expensive alternatives to ACA coverage, though the plans do not have to provide the same level of benefits. (Image: Shutterstock)

House Democrats sent letters to 12 insurance companies seeking information about health coverage they sell that critics refer to as “junk plans.”

President Donald Trump's administration last year expanded the availability of short-term, limited-duration health plans. Companies that received letters Wednesday from House Energy and Commerce Committee Chairman Frank Pallone of New Jersey and other committee leaders include Anthem Inc., UnitedHealth Group Inc., Health Insurance Innovations Inc. and closely held Cambia Health Solutions.

Health Insurance Innovations, an insurance brokerage that touts a cloud-based technology platform, saw its shares plunge 17 percent, giving it a market value of roughly $458 million. Anthem and UnitedHealth, who rank among the largest health insurers in the U.S., were each higher by more than 2 percent in afternoon trading.