A voluntary transfer of money, a negotiable instrument, or other thing by the obligor to the obligee, made as interest on or part payment of or collateral security for the antecedent indebtedness;

or债务人主动向债权人移交款项、流通票据、或者其他物品，以做先前债务的利息、部分付款、或者附加担保的；

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Furthermore, it was using a non-marketable instrument (the promissory notes) to provide collateral against these loans.

FORBES: Ireland's Promissory Note Deal