Commercial paper is a type of short term debt security usually issued as part of a commercial paper program. To satisfy the requirements of an exemption from registration under the Securities Act that commercial paper often relies on, the maturity of commercial paper relying on that exemption must not exceed 270 days.

A typical commercial paper program involves an issuer continuously rolling over its commercial paper, financing a more-or-less constant amount of its assets using commercial paper. The nine-month maturity limit is not violated by the continuous rollover of notes, as long as the rollover is not automatic, but is at the discretion of the issuer and the dealer.

For more information on US commercial paper programs, see Practice Note, US Commercial Paper Programs: Overview.