Banks finance their lending to risky firms by selling these loans to nonbank financial institutions. Among these nonbanks, collateralized loan obligations (CLOs) provide the bulk of funds. I show that CLO managers have significant market power during loan origination, which increases firms' cost of borrowing in the leveraged loan market. Akin to bank market power in classic lending relationships which are the result of a bank's "information monopoly," nonbank market power is the result of asymmetrically informed nonbanks. Information asymmetries across nonbanks arise from differential information flows during loan underwriting. Contrary to the underwriting of public securities, banks in general disseminate private information about the borrower when marketing a loan. However, some nonbanks self-restrict their information access to publicly available information. To identify my results, I construct a new instrument using novel data on mergers in the CLO industry. I provide the first analysis of these mergers and their determinants. Overall, this research highlights a key distinction between public and private debt markets and its economic consequences for borrowing firms. My findings have important implications for the ongoing legal debate on the applicability of securities law to leveraged loans.