Mark Nielsen (born 1964) is an American business executive, former government official, and attorney.
Nielsen's current position is Executive Vice President and Chief Legal Officer of Frontier Communications Corporation (NASDAQ: FTR), at the company's headquarters in Norwalk, Connecticut. With 2016 revenues of $8.9 billion, Frontier is America's fourth largest ILEC telephone company providing wireline voice, data and video services in 29 states. In 2016, Nielsen handled all legal aspects of Frontier's $10.5B acquisition of Verizon's wireline operations in California, Texas and Florida.
Nielsen started his legal career in 1990 as an associate lawyer at the Hartford law firm of Murtha, Cullina, Richter & Pinney, concentrating on federal and state litigation.
Nielsen's public roles have included Republican State Senator in Connecticut (1994 to 1998) and staff member to Mitt Romney when Romney was Governor of Massachusetts. Nielsen served as Romney's Chief Legal Counsel from 2004 to 2006, and his Chief of Staff from 2006 to 2007.
In his public roles, Nielsen earned a reputation for being fair-minded and willing to work across party lines. In his memoir, In My Time, Vice President Dick Cheney acknowledges that he was initially angered by favorable statements made by Nielsen during the 2000 presidential campaign about Cheney's opponent, Senator Joe Lieberman, but that, upon reflection, he couldn’t disagree with what Nielsen had said about Lieberman.
Nielsen is a graduate of Harvard College and Harvard Law School. His brother Steven Nielsen is CEO of Dycom Industries, Inc. (NYSE: DY).