Noteworthy Friday Option Activity: FIVN, UNH, MLYS

UnitedHealth (UNH) saw 67,042 options contracts trade today—about 6.7 million underlying shares, roughly 106.2% of its one‑month ADTV of 6.3 million—with concentrated activity in the $330 call expiring Dec. 26, 2025 (5,018 contracts ≈ 501,800 shares). Mineralys Therapeutics (MLYS) recorded 15,285 contracts (~1.5 million underlying shares, ~98.8% of its 1.5 million ADTV) led by the $60 call expiring Mar. 20, 2026 (5,108 contracts ≈ 510,800 shares). The flows point to sizable call-side positioning and speculative/options-driven demand in both names rather than fundamental corporate news.

Analysis

Market structure: the oversized option flow in UNH (67k contracts ≈6.7M shares, 106% of ADV) and MLYS (15k contracts ≈1.5M shares, ~99% of ADV) signals concentrated directional bets rather than broad retail nibbling. Short-delta hedging by market‑makers will create net buying pressure in the underlying into near-term rebalancing points, amplifying moves up to the strikes ($330 UNH, $60 MLYS) and compressing realised volatility if flows persist.

Risk assessment: primary tail risks are policy/regulatory shocks (Medicare/Medicaid pricing for UNH) and binary clinical/regulatory failures for MLYS; both could wipe >20–30% quickly. Time horizons split: immediate (days) — gamma-driven price impact; short-term (weeks–months) — option expiries concentrated in Mar/Dec 2026; long-term (quarters+) — fundamentals reassert; hidden risks include large block trades that are synthetics or covered positions that flip into selling at different deltas.

Trade implications: trade around gamma: bias long UNH exposure to capture dealer delta flows but prefer defined‑risk option structures (calendar or verticals) into earnings and policy windows. For MLYS treat as event‑driven spec: buy-levered, capped-loss call spreads into specific data/catalyst windows rather than naked longs; reduce brute equity weight in speculative biotech and rotate into higher-quality health insurers if seeking defensive growth.

Contrarian angles: consensus bullish read-through from volume may be flow-driven, not conviction-driven — the risk is an abrupt IV collapse when mark‑to‑market hedges unwind. Historical parallels (options-driven squeezes that reversed on IV contraction) suggest favoring defined‑risk spreads over naked exposure; mispricings likely in OTC liquidity and bid/ask, so trade size conservatively and anticipate 5–12% slippage in execution on these strikes.

Key Decisions for Investors

• Establish a 2% portfolio long position in UNH via a defined‑risk call vertical: buy UNH Dec 26, 2025 330/370 call spread sized to risk 2% of portfolio, target +10–15% upside by expiry, stop and reassess if UNH falls >8% from entry or if IV falls >30% relative.
• Speculative 0.5–1% position in MLYS: buy Mar 20, 2026 60/100 call spread (caps loss) ahead of any known clinical readouts, close or trim if no positive catalyst within 90 days or if implied vol >150% (take profits or convert to calendar).
• Tactical options income: sell short‑dated 30–45 day UNH call spreads (OTM) sized 0.5% if IV rank >50 and roll weekly; capture gamma/IV premium while maintaining limited upside risk — stop if underlying gaps >5% intraday.
• Pair trade: overweight UNH (as above) and short 0.8–1.0% position in HUM or a direct peer (e.g., HUM) to isolate insurer margin exposure; close the short if legislative risk (Medicare pricing headlines) increases in the next 60 days.