The Pious Fund was established by the Jesuits to finance missionary work in New Spain without having to rely on funding from the Spanish crown.  This "privatization" of Spanish conquest not only ensured independence of the Jesuit activities, it aroused suspicion.  There were many wealthy benefactors, but the fund was highly secretive, and no one knew how much it was actually worth.  After secularization, Mexico found itself heavily in debt to the fund for expropriated mission property.  To this day, Mexico is several millian dollars in arrears to the Catholic Church in California.