Video: Five major reflections 10 years after Citizens United

Nonprofit organizations with political agendas (known as 501(c)(4)s because of where they're described in the tax code), law firms and other limited liability corporations, and other entities are often used as "pass-through for the purpose of concealing the true sources of spending," said Erin Chlopak, director of campaign finance strategy at the Campaign Legal Center, which promotes tighter money-in-politics regulation. 

Watch the video here.