Mortgage-backed securities (MBS) means securities that are either:
(1) Pass-through securities or participation certificates that represent ownership of a fractional undivided interest in a specified pool of residential (excluding home equity loans), multifamily or commercial mortgages, or
(2) A multiclass security (including collateralized mortgage obligations and real estate mortgage investment conduits) that is backed by a pool of residential, multifamily or commercial real estate mortgages, pass through MBS, or other multiclass MBS.
(3) This definition does not include agricultural mortgage-backed securities guaranteed by Farmer Mac itself.
12 CFR § 652.5
For purposes of this subpart, the following definitions will apply: