Sia is a different word and is the singular present subjunctive of essere. "Penso che lui sia simpatico" (I think that he is likeable). You can also use "sia" in a "sia ... sia ..." or "sia ... che ..." construciton which means "both ... and ..."

SIA aims at designing, creating and managing competitive, secure and reliable transactional services in the areas of collections and payments, e-money, networking, trading and post-trading for banks, corporates, public administration bodies, central institutions and capital markets.