Select Medical Holdings Corporation (SEM) Gamma Exposure (GEX) & Greeks
Gamma exposure (GEX) analysis shows how options positioning creates dealer hedging pressure across strikes. Includes delta, vanna, charm, vomma, and vega exposure by strike price.
Select Medical Holdings Corporation (SEM) operates in the Healthcare sector, specifically the Medical - Care Facilities industry, with a market capitalization near $2.04B, listed on NYSE, employing roughly 30,000 people, carrying a beta of 0.80 to the broader market. Select Medical Holdings Corporation, through its subsidiaries, operates critical illness recovery hospitals, rehabilitation hospitals, outpatient rehabilitation clinics, and occupational health centers in the United States. Led by Thomas Mullin, public since 2009-09-25.
Snapshot as of May 15, 2026.
- Spot Price
- $16.51
- Net Gamma
- -$26.2K
- Net Delta
- $46.7K
- Net Vega
- -$1.7K
- Gamma Concentration
- 0.58
As of May 15, 2026, Select Medical Holdings Corporation (SEM) has negative net gamma exposure of $26.2K under the standard dealer-hedging convention. Net delta exposure is $46.7K. Negative GEX means dealers are net short gamma: they must sell into weakness and buy into strength, amplifying realized volatility and accelerating directional moves.
SEM Strategy Sizing in the Current GEX Regime
Select Medical Holdings Corporation is in a negative dealer-gamma regime ($26.2K). Net dealer delta of $46.7K sets the size of the directional hedging flow that fires as spot moves. In this regime, momentum and breakout strategies fit the regime: long calls or puts, ratio backspreads, calendar spreads positioned for vol expansion. Realized volatility tends to overshoot implied during negative-gamma stretches, hurting indiscriminate short-vol exposure. The gamma-flip level - the spot price at which net dealer gamma changes sign - is the most actionable anchor for sizing: through-flip moves trigger qualitatively different hedging behavior than within-regime moves, so risk-defined structures sized to the current spot may not stay sized correctly if a flip is near.
Learn how gamma exposure is reported and how to read the data →
Frequently asked SEM gamma exposure (gex) & greeks questions
- What is the current SEM gamma exposure (GEX)?
- As of May 15, 2026, Select Medical Holdings Corporation (SEM) net gamma exposure is negative at $26.2K under the standard dealer-hedging convention. Net dealer delta exposure is $46.7K. GEX aggregates the gamma sitting on dealer books across all listed strikes and expirations.
- Is SEM in positive or negative dealer gamma right now?
- SEM is currently in negative dealer gamma. Dealers net short gamma must sell into weakness and buy into strength to maintain delta-neutrality, which amplifies realized volatility and tends to accelerate directional moves.
- What does SEM GEX tell options traders?
- GEX is a regime indicator: positive-gamma regimes favor mean-reverting strategies (premium-selling near established ranges); negative-gamma regimes favor momentum and breakout strategies. The same options-strategy structure can be appropriate or inappropriate depending on the dealer-gamma regime, so reading the sign and magnitude of net GEX before sizing positions is standard practice.