Theories of financial intermediation predict that bank loans should no
t be marketable because of moral hazard problems; banks will not condu
ct credit risk analysis or monitor borrowers if they are not at risk f
or failing to perform these services. Throughout most of history, bank
loans have not, in fact, been marketable. Yet, by the end of the 1980
's the amount of commercial and industrial loan sales outstanding had
grown to over $250 billion from trivial amounts at the beginning of th
e decade. To explain the opening of this loan sales market, we present
a model of incentive-compatible loan sales that allows for implicit c
ontractual features between loan sellers and loan buyers. We then test
for the presence of these features using a sample of over 800 recent
loan sales.