Early Uber investor Bradley Tusk on why he plans to sell some of his shares

For the first time since the company went public, Uber investors are allowed to unload shares on Wednesday Nov. 6. In the six months since the IPO, Uber shares have tanked by almost 38 percent. Bradley Tusk, founder and CEO of Tusk Ventures, was an early investor in Uber and he joins "Squawk Box" to discuss the expiration of the lockup.