Matthew Hogan, Ciphergen's chief financial officer, has resigned, according to documents filed by the company with the US Securities and Exchange Commission last week.
Hogan will "provide consulting services" to the company and receive his current salary for up to six months, according to the filing.
Daniel Caserza was named interim CFO. Caserza joined Ciphergen in 1999. He became a vice president in April 2005.