At least for the first day, this was documented (and expected) from the underwriters. http://www.businessinsider.com/facebook-banker-morgan-stanley-bought-a-hum

At least for the first day, this was documented (and expected) from the underwriters. http://www.businessinsider.com/facebook-banker-morgan-stanley-bought-a-humongous-amount-of-stock-to-try-support-price-2012-5 http://www.businessinsider.com/facebook-banker-morgan-stanle... Underwriters start out with a net short position on an IPO so that they can step in to support if necessary.