X0609 4 2026-09-15 0001396440 Main Street Capital CORP MAIN 0001069725 FOSTER VINCENT D false 1300 POST OAK BLVD 8TH FLOOR HOUSTON TX 77056 true false false false 0 Common Stock 2026-09-15 5 J 0 13.6287 56.37 A 1677690.8778 D Common Stock 2026-09-15 5 J 0 1114.3552 56.37 A 1678805.2330 D Common Stock 2026-09-28 5 J 0 15.8584 55.10 A 1678821.0914 D Common Stock 2026-09-28 5 J 0 1296.6786 55.10 A 1680117.7700 D Common Stock 2026-09-15 5 J 0 85.1549 56.3700 A 71256.5061 I MS Trust I Common Stock 2026-09-28 5 J 0 99.0873 55.10 A 71355.5934 I MS Trust I Common Stock 2026-09-15 5 J 0 164.9612 56.37 A 35427.7194 I MS Trust II Common Stock 2026-09-28 5 J 0 191.9510 55.10 A 35619.6704 I MS Trust II Common Stock 2026-09-15 5 J 0 85.1549 56.37 A 70506.0319 I MS Trust III Common Stock 2026-09-28 5 J 0 99.0873 55.10 A 70605.1192 I MS Trust III Common Stock 33300 I MS Trust V The reporting person acquired these shares under a dividend reinvestment plan, pursuant to a dividend reinvestment transaction exempt from Section 16 under Rule 16a-11. Family trust /s/ Jason B. Beauvais, Attorney-in-Fact 2026-10-20