Galantino, who has been president of APSA since June 2018, said the book did not reflect the real situation.
"In fact," he said, "the ordinary management of the APSA in 2018 closed with a profit of over 22 million euros."
He attributed reported losses on "an extraordinary intervention aimed at saving the operation of a Catholic hospital and the jobs of its employees," in an apparent reference to the IDI loan and purchase.
While Galantino defended the project as an effort to preserve the hospital and save jobs, APSA's involvement to underwrite a commercial acquisition appears to violate a 2012 commitment to stop acting as a private or commercial financial institution.
That commitment was the result of an on-site inspection by Moneyval, the Council of Europe's Committee for combating money laundering and terrorist financing.
After the inspection, APSA agreed to stop providing services to individuals or taking part in commercial transactions, with these functions being transferred to the Institute for Religious Works (IOR), often referred to as the Vatican Bank, which maintains accounts for Vatican employees, individuals and religious groups. APSA was to be limited to administering the sovereign assets of the Holy See, meeting payroll and operational costs, and functioning as the national reserve bank of the Vatican.
In exchange for agreeing to step back from commercial activity, APSA was exempted from annual inspections by the Vatican's Financial Intelligence Authority (AIF), whose efforts are assessed by Moneyval.
Following the changes to APSA's remit, only the IOR, and not APSA, has been listed as a financial institution under the oversight of the Vatican's Financial Intelligence Authority (AIF), whose efforts are assessed by Moneyval.
In 2014, Pope Francis issued new norms, transferring oversight and control of APSA's remaining investment functions to the Prefecture for the Economy, then headed by Cardinal George Pell.
The AIF's 2015 annual report concluded that since it is no longer an "entity that carries out financial activities on a professional basis," "APSA stopped being a part of AIF's jurisdiction at the end of 2015" - but in the same year APSA made the loan to purchase the IDI out of insolvency.
The 2015 AIF report which exempted APSA from further scrutiny said that "If APSA were to carry out financial activities on a professional basis, it would fall again under the jurisdiction of AIF which… must publish and update the list of subjects who must comply with the requirements set forth in [relevant law]."
The acknowledgement by Galantino that APSA was in 2015 engaged in prohibited lending activity casts doubt over reported progress in combating financial corruption in the Vatican, and suggests that it has been operating out of sight of Vatican and European financial watchdogs.
In 2016, Pope Francis partially reversed some of the 2014 reforms, returning control of its investment activity to APSA from the Prefecture for the Economy.
In his book released Monday, Nuzzi also claimed that, despite the 2012 commitment to Moneyval, APSA still has private numbered accounts for individuals on deposit. Such accounts at APSA have been linked to previous money laundering accusations and scandals in the Vatican, and their elimination was crucial to its exemption from AIF oversight.
Galantino denied these claims, saying that no funds were held, managed or invested for anyone or any body except Vatican departments and the Vatican City State.
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"APSA has no secret or encrypted accounts" Galantino insisted on Tuesday, "anyone is welcome to prove the contrary."
Definitive proof is unlikely to emerge, barring a decision by the AIF to reapply Moneyval's anti-money laundering regulations and inspections to APSA - something which is itself highly unlikely in the current climate.
Three weeks ago, Tomasso Di Ruzza, head of the AIF, was himself suspended following raids carried out by Vatican police. On Oct. 23, the AIF issued a statement announcing his return to duty and insisting that an internal investigation had been conducted following the raid and that no wrongdoing had been discovered.
"Neither the Director nor any other employee of AIF improperly exercised his authority or engaged in any other wrongdoing," the statement said.
"Accordingly, the Board of Directors reaffirms its full faith and trust in the professional competence and honorability of its Director and, moreover, commends him for the institutional work carried out in the handling of this particular case."
The statement concluded by saying the AIF hoped any "potential misapprehensions" to the contrary would "soon be clarified."