The billionaire investor is under two subpoenas from the House Oversight Committee. But in his lawsuit, Black says the panel doesn't have the authority to compel him to share nondisclosure agreements.

Black refused to appear for a scheduled deposition in front of the House Oversight Committee.

The billionaire investor is under two subpoenas from the House Oversight Committee. But in his lawsuit, Black says the panel doesn't have the authority to compel him to share…