The lines between public and private companies are blurring, says Adam Oliveri, managing director, private company market at SecondMarket Holdings Inc., one of the new marketplaces where stock in private companies, such as Facebook Inc., are bought and sold. As secondary markets have grown, the Securities and Exchange Commission has begun to pay more attention to them and is currently looking into whether or not funds focused on individual private company stocks are being created to skirt registration requirements. In this video interview with The Deal magazine, Oliveri says SecondMarket has seen no evidence of that. For more on the rules that govern private stock trading, see "Liquidity now" by veteran legal reporter David Marcus, and for more on how Facebook and other social media companies are staying private as long as they can, see "The warmth of the nest." - Mary Kathleen Flynn