Definition of Money Market Certificate (MMC)

nonnegotiable certificate of deposit with a minimum denomination of $2,500 and an original maturity of at least seven days. Prior to January 1983, when the MMC was deregulated, the account was a six-month CD requiring an initial deposit of $10,000 to open an account, and paying a rate tied to the yield on six-month U.S. Treasury bills. With deregulation, maturities and rates paid depositors are set by management policy in individual financial institutions, not by government regulation.