X0306 4 2015-11-12 0001621434 Black Stone Minerals, L.P. BSM 0001636921 Longmaid John H. 1001 FANNIN STREET, SUITE 2020 HOUSTON TX 77002 true false false false Common units representing limited partner interests 2015-11-12 4 P false 20000 13.7418 A 1047347 I By The Longmaid Family Trust Common units representing limited partner interests 353652 I By John H. Longmaid 1965 Trust Common units representing limited partner interests 219479 I By John H. Longmaid 1968 Trust The price reported in Column 4 is a weighted average price. These common units were purchased in multiple transactions at prices ranging from $13.34 to $14.11, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of common units purchased at each separate price within the ranges set forth in this footnote. In a previous transaction that was not reportable on Form 4, Mr. Longmaid transferred 5,263 common units owned directly to the Longmaid Family Trust. /s/Steve Putman, Attorney-in-Fact for John H.Longmaid 2015-11-16