Blunt presses HHS for data on ObamaCare premiums

"These negotiations have been conducted behind closed doors, without assurances that a fair process has been observed or that the negotiations will result in better insurance products for consumers," Blunt said in a letter to HHS Secretary Kathleen SebeliusKathleen SebeliusThe House needs to help patients from being victimized by antiquated technology Obama cabinet official: Clinton White House doubled down on 'abusive behavior' John Roberts has tough job of keeping faith in Supreme Court MORE.

He asked the department to release all rate filings from insurers that applied to sell plans in the 34 federally run exchanges. 

He also sought more information about HHS's negotiations with insurance companies, including "any incentives HHS used to motivate insurers to change their rates."

HHS had said it would not actively negotiate with plans. Officials have described the current negotiations as modest, saying officials are mostly pointing out when insurers come in higher or lower than the average premium in a given market.