Notable Thursday Option Activity: BURL, CHWY, MCK

Chewy (CHWY) saw unusually heavy options activity with 38,828 contracts traded (~3.9M underlying shares), equal to ~49.2% of its one‑month ADV of 7.9M shares; the $25 put expiring March 20, 2026 accounted for 16,306 contracts (~1.6M shares). McKesson (MCK) recorded 3,879 contracts (~387,900 shares), about 48% of its one‑month ADV of 808,715 shares, led by 1,024 contracts in the $950 put expiring Feb 20, 2026 (~102,400 shares). The concentrated put flows point to elevated speculative/hedging activity and could signal near‑term bearish positioning or risk management interest in both stocks.

Analysis

Market structure: The concentration of put activity (CHWY Mar-20-2026 $25: 16,306 contracts ≈1.6M shares ≈49% of ADV; MCK Feb-20-2026 $950: 1,024 contracts ≈102.4k shares ≈48% of ADV) signals one or a few large directional or hedging trades rather than broad retail flows. Immediate effect: increased demand for downside protection will push up implied volatility and put skew for these tickers over the next 1–8 weeks, creating wider bid/ask and transient liquidity dislocations. Net winners are put buyers and liquidity providers; losers are long-equity retail holders and delta-hedgers forced to sell into weakness if these are directional buys.

Risk assessment: Tail risks include company-specific shocks (CHWY: margin compression from freight/competitive pricing; MCK: regulatory/drug-pricing action) or a macro risk-off that re-prices vol across names; either could move stock >30% within 3–6 months. Short-horizon (days–weeks) risk is IV spikes and gamma-driven price moves; medium-term (months) risk is fundamental deterioration; long-term (quarters) depends on earnings/EBITDA trajectory. Hidden dependency: if these are structured-product hedges, unwind could be sudden, reversing IV and price moves within 1–3 trading days.

Trade implications: For CHWY, favor a defined-risk long-vol play: buy Mar-20-2026 $25/$20 put debit spread sized to 1–2% portfolio risk (target 50–100% upside, stop at 50% premium loss), or buy the $25 puts outright if willing to hold 6–12 months. For MCK, prefer a smaller directional hedge: buy Feb-20-2026 $950/$900 put spread (0.5–1% portfolio) only if IV is <40% above 30-day mean; otherwise sell 3–6 week call spreads to finance longer-dated protection. For macro rotation, increase healthcare vs consumer staples/retail exposure by +1–2% if these flows presage a broader risk-off.

Contrarian angles: The block-size puts may be risk-management (collar/structured) not bearish alpha — if sellers were option dealers, forced delta-hedging could create a short-term downward spiral that reverses on unwind. Market may be overpricing sustained downside: if CHWY shares do not gap lower within 2–4 weeks, IV should mean-revert 20–40%; that provides an opportunity to sell premium (calendar/iron condor) into elevated vols. Historical parallel: large put blocks in single names often precede 10–25% mean reversion within 1–3 months once gamma flows normalize.

Key Decisions for Investors

• Establish a defined-risk long-vol position in CHWY: buy Mar-20-2026 $25/$20 put debit spreads sized to 1–2% of portfolio risk; set take-profit at +50–100% and cut at -50% of premium within 6–12 months.
• For MCK, place a tactical hedge: buy Feb-20-2026 $950/$900 put spread sized to 0.5–1% of portfolio if implied vol is ≤40% above 30-day average; otherwise use short-dated call spreads (3–6 weeks) to fund protection and reduce carry.
• Implement a pair trade: rotate +1–2% portfolio weight into healthcare (MCK, UNH) and -1–2% out of consumer discretionary (CHWY, BURL) for 1–3 months, re-evaluate after next earnings or if CHWY IV mean-reverts >30%.
• If CHWY or MCK implied volatility remains elevated (>30–40% above 30-day mean) for >4 weeks, sell calendar/iron-condor structures to collect premium-sized to 0.5–1% of portfolio with strict vega and gamma limits.