Margin Operations

This walks you through margin calculations and operations for brokerage accounts, covering both the regulatory requirements (Reg T initial margin, FINRA maintenance rules) and practical mechanics like SMA calculations, buying power, and margin call procedures. Use it when you're building margin systems, need to understand the difference between fed calls and house calls, or want to figure out portfolio margin eligibility under OCC TIMS. It covers the full spectrum from basic 50% initial requirements through complex portfolio margin stress scenarios and forced liquidation waterfalls. The detail on pattern day trader rules and concentrated position margin is solid if you're dealing with active trading accounts or risk management workflows.