An agency trade is a transaction where a brokerage firm acts as a middleman, or agent, on behalf of a client to buy or sell securities. Think of your broker as a real estate agent for stocks. When you want to buy a house, the agent doesn't sell you one from their own portfolio; they go out into the market to find a house that matches your criteria and facilitate the purchase from a third-party seller. Similarly, in an agency trade, the broker goes to a stock exchange or another trading venue to execute your order with another market participant. The broker never owns the security themselves in the process. For this service, the broker is compensated with a fee, typically a commission. This model is the most common way retail investors interact with the market. The core principle is that the broker is working for you, with a fiduciary duty to secure the best possible price on your behalf.
Understanding the difference between an agency trade and its counterpart, the principal trade, is crucial for any investor. It reveals who you are really trading with and where potential conflicts of interest might lie.
In an agency trade, your broker is your agent. Their job is to represent you in the market. They take your order and find a counterparty to complete the transaction. In a principal trade, your broker acts as the dealer. They are the counterparty. If you are buying, you are buying directly from the broker's own inventory. If you are selling, you are selling directly to the broker, who adds the securities to their inventory. Firms that do this are often called market makers.
The key difference comes down to who bears the risk of holding the security.
This is where the rubber meets the road for investors.
For a value investor, who prizes discipline, transparency, and cost control, the distinction is fundamental.