From the Collaborative Bond and Money Market Data Portal
In the Collaborative Bond and Money Market Data Model, "Placement Type" expresses how the debt instrument was sold. The model distinguishes the following types.
Syndicated Placement - where the Debt instrument (Bond, Note, MTN, CP, CD, Bill) was sold through a syndicate of more than one primary market dealers.
Auction Placement - where the Debt instrument (Bond, Note, MTN, CP, CD, Bill) was sold through a Dutch or other type auction format.
Private Placement Self Led - where the Debt instrument (Bond, Note, MTN, CP, CD, Bill) was sold by a primary market dealer that belongs to the same Group as the Issuer.
Private Placement 3rd Party - where the Debt instrument (Bond, Note, MTN, CP, CD, Bill) is sold by a primary market dealer that does not belongs to the same Group as the Issuer.
Placement not known - where it is not known which primary market dealer sold the Debt instrument (Bond, Note, MTN, CP, CD, Bill).