David Hahn, the former VP of product for LinkedIn(s LNKD), will join Greylock Partners as an entrepreneur-in-residence, the VC firm announced Monday. At LinkedIn, Hahn oversaw the company's monetization products, including Sponsored Updates. According to LinkedIn co-founder and current Greylock partner Reid Hoffman, Hahn's product portfolio generated $1.5 billion for the company. As an entrepreneur-in-residence, Hahn will advise the leadership teams of the firm's portfolio companies, which include both social and enterprise startups, on monetization and product.