X0609 4 2026-06-30 1 0001320414 SELECT MEDICAL HOLDINGS CORP SEM 0001212986 CARSON RUSSELL L false C/O WELSH, CARSON, ANDERSON & STOWE 599 LEXINGTON AVE., SUITE 1800 NEW YORK NY 10022 true false false false 0 Common Stock 2026-06-30 4 J 0 610035 0 D 0 D This Form 4 reports securities disposed of under the Agreement and Plan of Merger (the "Merger Agreement"), entered into on March 2, 2026, by and among the Issuer, Stallion Intermediate Corporation ("Parent"), and Stallion MergerSub Corporation (filed as Exhibit 2.1 to the Form 8-K filed with the Securities and Exchange Commission on March 3, 2026). Immediately prior to the effective time of the merger, the Reporting Person contributed 610,035 common shares (including 14,035 restricted shares which vested immediately prior to the effective time of the merger) to Parent in exchange for an equivalent amount of shares of common stock ("Parent Common Shares") of Parent, which Parent Common Shares were then exchanged for an equivalent amount of interests in Stallion Group Parent, LP. /s/ John F. Duggan, Attorney-in-Fact 2026-07-01