TransMedics Group Plummets 10%—What’s Driving the Sell-Off?

• TMDX shares collapse 9.77% intraday to $112.59, erasing $424M market cap
• 52-week range remains $55–$177.37; 200-day MA at $94.35 now 18% below current price
• Institutional buying surged in Q1 with Vontobel adding $291K position
• Analysts upgraded rating to 'Hold/Accumulate' despite negative technicals

TransMedics Group’s brutal selloff on July 11 marks its worst single-day performance in months, testing critical support levels as short-term bears dominate. The stock’s 3.37% volatility range ($109.59–$123.50) highlights extreme intraday tension ahead of key technical thresholds.

Bearish Technicals & Pivot Break Trigger Massive Sell-Off
The collapse stems from converging technical breakdowns: the stock violated a critical $124.00 support level established by accumulated volume, while its 30-day moving average ($131.59) now acts as resistance. The MACD histogram’s -1.66 divergence confirms bearish momentum, amplified by a descending 200-day MA that’s now 23% below current prices. Analysts note the June 12 pivot top’s 12.77% decline as confirmation of a broader downtrend, with resistance clusters at $126.87 and $130.57 exacerbating selling pressure.

Bullish Put Spreads & Technical Breakpoints Offer Contrarian Opportunities
TMDX20250718P105 (Put, $105 strike, expiring July 18):
• Implied Volatility Ratio: 69.35%
• Delta: -0.227 | Gamma: 0.026 | Theta: -0.070
• Turnover: $4,388 | Leverage Ratio: 70.43%

TMDX20250815P115 (Put, $115 strike, expiring August 15):
• Implied Volatility Ratio: 85.76%
• Delta: -0.470 | Gamma: 0.013 | Theta: -0.088
• Turnover: $39,007 | Leverage Ratio: 8.60%

Bullish put spreads capitalize on the $124.00 support test. For a 5% downside scenario to $107.00:
- July 18 $105 put payoff: $1,800 max gain (max loss: -$3,460)
- August 15 $115 put payoff: $8,000 max gain (max loss: -$2,920)
Bulls should monitor $117.92 20-day Bollinger Band support; shorts target $109.59 breakdown. Aggressive traders may pair the July 18P105 with a protective stop at $120.18 (4.49% below).

Backtest TransMedics Group Stock Performance
The backtest of TMDX's performance after a -10% intraday plunge shows favorable results, with win rates increasing significantly across various time frames. The 3-Day win rate is 53.35%, the 10-Day win rate is 55.59%, and the 30-Day win rate is 59.42%. This indicates that TMDX tends to recover from such significant dips, with the maximum return observed being 18.63% over 30 days.

Hold the Line at $124—or Prepare for a Sector Shakeout
TransMedics’ fate hinges on holding the $124.00 psychological support. A breach could trigger a freefall toward $105, while reclaiming the $126.87 resistance would revive institutional interest. Monitor Medtronic (MDT +0.37%)’s performance as a sector bellwether—its minor uptick suggests cautious optimism in healthcare equipment. Investors should prioritize put spreads and tighten stops as volatility contracts. Bottom line: This is a battle for the $120–$125 pivot zone—break it, and the next bearish chapter begins.