Primary Dealer Market Maker
A financial institution appointed to participate in and support the market for Nigerian government securities under applicable rules.
Example: A PDMM submits bids and provides secondary-market liquidity.
PDMMs are the banks and dealing firms the DMO appoints as the wholesale channel for federal government securities. They carry two obligations: bid at every auction, and quote two-way prices in the secondary market so that other investors can trade.
This structure explains why you cannot buy an FGN bond from the government directly. Auctions are built around the PDMMs. Your bank or stockbroker aggregates retail orders and routes them through a PDMM, or sells you securities from its own holdings.
The market-making obligation is what gives FGN bonds and treasury bills their liquidity. When you sell a bill before maturity, a PDMM's bid is usually the price you get.
For a retail investor the practical takeaway is simple: the PDMM list on the DMO website doubles as a list of institutions with direct access to government securities. If you want to buy at auction rather than secondary prices, open the account with one of them or with a broker that routes through one.