📖Jim Simons

Sell Discipline Rules

🌿 Intermediate★★★★★

Follow pre-defined sell criteria without emotion.

💬

Have clear, pre-defined sell criteria. Sell when: your thesis is broken, valuation is fully realized, or a significantly better opportunity appears.

— The Man Who Solved the Market,2019

🏠 Everyday Analogy

A process is like a pilot checklist: discipline prevents simple mistakes when pressure rises and keeps outcomes more repeatable.

📖 Core Interpretation

Jim Simons advocates a repeatable process: define criteria, execute consistently, and review decisions against evidence. Process quality drives outcome consistency.
💎 Key Insight:Disciplined selling prevents emotional decision-making.

AI Deep Analysis

Get personalized insights and practical guidance through AI conversation

❓ Why It Matters

Without process, there is no reliable feedback loop. Structured execution and review improve decision quality over time.

🎯 How to Practice

Run a decision loop of research, thesis, execution, and post-mortem; document assumptions and update playbooks with evidence, not hindsight bias.

⚠️ Common Pitfalls

Having opinions without execution criteria
Reviewing outcomes but not decisions
Abandoning rules during volatility spikes

📚 Case Studies

1
Airports and Urbanization (2016)
Backed European and Asian airport operators benefiting from low-cost carriers and emerging market travel demand
✨ Outcome:Passenger growth and regulatory clarity supported rising cash flows, leading to both dividend growth and capital appreciation
2
Medallion Fund Capacity Limits (1997)
As Medallion’s assets grew, Simons recognized diminishing returns from crowding in short-term strategies and imposed strict capital caps.
✨ Outcome:Capping AUM preserved edge, leading to sustained exceptional returns while newer capital was diverted to less capacity-constrained strategies.

See how masters handle real scenarios?

30 real investment dilemmas answered by legendary investors

Explore Scenarios →