Defining the Distinction
Market-making involves facilitating customer trades — providing liquidity to buyers and sellers who want to trade. Proprietary trading involves trading for the firm's own account based on directional views about price movements. In practice, the line can be blurry: a market maker that maintains large inventory positions is, in effect, taking directional risk similar to proprietary trading.
The Volcker Rule Context
The Volcker Rule prohibits banks from engaging in proprietary trading. Banks that engage in market-making are exempt, but only if the market-making is genuinely customer-facilitated rather than speculative. Non-bank market makers like Citadel Securities are not subject to the Volcker Rule.
Information Barriers and Affiliated Entities
Citadel Securities (market maker) and Citadel Advisors (hedge fund) are legally separate entities under Griffin's ownership, with regulatory information barriers. The concern that market-making operations could benefit from hedge fund insights — or that market-making order flow information could benefit the hedge fund — is addressed by these barriers, though their adequacy has been questioned.
Regulatory Oversight of Firm Activities
FINRA oversight of Citadel Securities focuses on its registered broker-dealer activities. The distinction between legitimate market-making and potential proprietary speculation is a subject of examination. Regulators assess whether market-making activities are genuinely customer-facilitated or whether the firm's own account trading crosses into prohibited or conflicted territory.