A little noticed change went into effect July 3:
Counterparties that issue eligible bank bonds guaranteed by an EEA public sector entity with the
right to impose taxes may not submit such bonds or similar bonds issued by closely linked entities
as collateral for Eurosystem credit operations in excess of the nominal value of these bonds already
submitted as collateral on the day this Decision enters into force.
This means that banks may no longer issue debt to themselves, pay the government a guarantee fee, and then pledge those securities to their local NCB for financing. Italian banks issued these after an enabling law was passed by PM Monti's new government in December. As of March, €77 billion was borrowed from the Bank of Italy using this collateral.
The ECB's decision to expand collateral rules for certain asset backed securities may have attracted more attention, but this change could be more important.