The initials "p.p." stand for "per procurationem." It is a common legal and business practice where a person can grant secretaries or other third parties the authority to sign documents on his behalf.
A typical way this is used in business documents is: "p.p. Secretary's Signature" one line above "President's Name." Alternatively, the president's typed name can precede the secretary's signature. Executives often delegate their authority to sign documents if they are unavailable or too busy. People who are too ill to handle their own affairs can grant power of attorney to another person of their choice. The designated party can sign documents on the incapacitated person's behalf, and it will be legally binding.