Protective Put

Core Thesis

A Protective Put buys crash insurance on long stock. It converts open-ended downside into a defined floor while preserving upside participation.

Structure

• Long 100 shares at $S_0$.
• Long 1 put at strike $K_p$ for premium $P_0$.
• Common use: hedge around uncertain events without liquidating core holdings.

Expiration Payoff Mathematics

$$\Pi_T = (S_T - S_0) + \max(K_p - S_T, 0) - P_0$$

• Max loss: $S_0 - K_p + P_0$.
• Break-even: $S_0 + P_0$.
• Max profit: unlimited upside minus hedge cost.

Greek Profile

• Net delta remains positive but declines as downside accelerates.
• Net gamma positive on downside because put grows in sensitivity.
• Net theta negative due to insurance premium decay.
• Net vega positive (vol spikes support hedge value).

Hedge Design

• Choose strike by tolerated drawdown, not by premium alone.
• Match tenor to risk window; avoid overpaying long-dated protection if catalyst is near-term.
• Consider rolling rules before hedge decays into low-delta protection.

Management Framework

• If event passes and risk premium collapses, monetize put and reassess.
• For long-term programs, run systematic rolling schedule and track annual hedge carry.
• Blend with covered calls/collars when carrying cost must be reduced.

Failure Modes

• Buying protection after volatility has already spiked.
• Selecting strikes too far OTM, creating psychological but not economic protection.
• Letting hedge expire unmonitored during continuing risk window.

Practical Checklist

• What specific loss floor is required at portfolio level?
• Is hedge tenor aligned with the actual risk horizon?
• Is premium spend acceptable as recurring insurance carry?