We study a known negative signal, the sale of insider shares in an IPO and find that insiders adopt two concealment strategies consistent with wealth-maximizing behavior. First, insiders underreport the number of personally owned shares in the prominent original prospectus and use an obscure amendment to communicate the true higher level of shares to be offered. Second, when insiders increase shares in a later amendment, they tend to either increase secondary shares disproportional to primary share increases, or to reduce primary shares to wholly or partly conceal the increase in secondary shares offered. Insiders confound the negative secondary share signal by simultaneously sending a positive lockup signal.