Clayton's Case

The rule in Clayton's Case (or, to give it its full legal name and citation: Devaynes v Noble (Clayton's Case) (1816) 1 Mer 572) is a common law presumption in relation to the distribution of monies from a bank account. The rule is based upon the deceptively simple notion of first-in, first-out to determine the effect of payments from an account, and will normally apply in the absence of evidence of any other intention.
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An English case which established a presumption that monies withdrawn from a money account are presumed to be debits from those monies first deposited; first in, first out. - (read more on Clayton's Case)