Mandate-based sourcing is the institutional pattern. A broker representing five buyers in parallel runs five mandates, not one pipeline-of-everything. Each mandate has its own buy-box (above), its own gate criteria, its own decision history (PASS / FAIL / PENDING with reasons), and its own audit trail so the broker can defend the pipeline to the buyer's analyst or IC.
The mandate model collapses for most brokers around the third or fourth simultaneous client when they try to manage it in a single spreadsheet. The systems that scale past five mandates treat each as a structured workspace with the buy-box explicit, gates written down, and decisions logged rather than recalled.
