A 'financial instrument' varies, and in your text, this will depend on what in particular the Provider is assigning/transferring to the Receiver. Your context (leasing) suggests some document that represents a legally enforceable, binding agreement between two (or more) parties with regard to a right to payment of money, that the Receiver gets. in the term of assignments: the nature/type of financial instrument will be in accord with what is actually being transferred to the Receiver.
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