According to a ZDNet report, Nathan Francis Wyatt, 39, who is part of an infamous hacking group known as The Dark Overlord (TDO), was arraigned in a Saint Louis court on Wednesday where he pleaded not guilty.
"US authorities believe Wyatt was one of the many TDO members who, since 2016, have been hacking US companies, stealing their data, and asking for huge ransoms," the report said.
If not paid, Wyatt would put the data up for sale or tip journalists about the breach to generate negative coverage for the hacked firms, mostly health care companies.
The TDO group is known for its aggressive extortion campaigns.
In 2018, TDO members sent bomb threats to schools in Montana which refused to pay ransom demands.
The Dark Overlord also stole information on about 200,000 former patients of the Athens Orthopedic Clinic in 2016.
The group demanded $75,000 in bitcoin from one health care company and 400,000 British pounds from another, records from the extradition case said.
Wyatt was previously arrested by the UK police in September 2016 on suspicion of hacking the iCloud account of Pippa Middleton, the sister of the Duchess of Cambridge.
The Dark Overlord has also claimed credit for the release of stolen episodes of Netflix's "Orange is the New Black".
( With inputs from IANS )