Stamps.com finished its Series A funding in February 1998 with $1.5 million. Series B funding followed in August 1998 with $4.52 million. It had its last round of private financing in February 1999, generating an additional $30 million from investors including former Postmaster General, Marvin Runyon. The company went public in June of the same year and raised $55 million in its IPO. Less than six months after its IPO, the company had its secondary public offering. In August 1999, the Postal Service granted permission for Stamps.com to sell its service nationally. Stamps.com purchased IShip.com, a company that compared prices of shipping services, for $305 million in stock or eight million shares, in October 1999.