5 Under-the-Radar Picks from David Einhorn That Are Quietly Dominating 2026

In this article, we will list the 5 under-the-radar picks from David Einhorn that are quietly dominating 2026. Please visit 15 Under-the-Radar Picks from David Einhorn That Are Quietly Dominating 2026 if you would like to see the extended list and the methodology behind it.

5. Acadia Healthcare Company, Inc. (NASDAQ:ACHC)

Greenlight Capital’s Stake: $59 Million 

Increase in Share Price Over Past Six Months: 21%

Acadia Healthcare Company, Inc. (NASDAQ:ACHC) is a relatively recent addition to the 13F portfolio of Greenlight Capital. The fund first disclosed a stake in the company in the fourth quarter of 2024. This position comprised a little over 128,000 shares. In three of the next four quarters, the fund added to this position. Filings for the fourth quarter of 2025 show that the fund owned 4.1 million shares in the firm, up 150% compared to filings for the third quarter of 2025. The company provides behavioral healthcare services in the United States and Puerto Rico. It owns and operates acute inpatient psychiatric facilities, specialty treatment facilities comprising residential recovery facilities and eating disorder facilities, as well as comprehensive treatment centers and residential treatment centers.

Acadia Healthcare Company, Inc. (NASDAQ:ACHC) is currently the largest stand-alone behavioral healthcare provider in the US, a sector with high barriers to entry. In 2025, the firm added 1,089 beds through new openings and expansions. For 2026, management has committed to adding another 400 to 600 beds. Hedge funds view this physical moat as a primary driver for long-term organic growth. As occupancy increases across these new sites, the incremental revenue is expected to drop to the bottom line at high margins since the overhead is already covered.