Armstrong and the government both have subpoenaed Nike, which was one of Armstrong's major sponsors until it dropped him in 2012 after his use of performance-enhancing drugs was exposed.
The government is suing Armstrong to recover more than $30 million the U.S. Postal Service paid to sponsor his teams from 1998-2004. Damages could go as high as $100 million. The lawsuit was initially filed by former Armstrong teammate Floyd Landis, who stands to collect a portion of any penalty against Armstrong.