Black Stone Minerals, L.P.

Activity Update

Development Activity

As of the end of the third quarter, Adamas Energy ("Adamas") was operating two rigs on Black Stone’s Angelina and San Augustine acreage in the Shelby Trough. During the third quarter, Adamas successfully turned to sales 7 gross (0.7 net) wells. Adamas’s development program remains on track with the development agreements, with a total of 14 wells spud in the previous program year that ended on June 30, 2026. Of these wells, 9 gross (0.9 net) have turned to sales as of September 30, 2026, and 4 gross (0.4 net) are expected to turn to sales during the fourth quarter of 2026, with the remaining well under further evaluation. As of September 30, 2026, Adamas spud 6 of the total 17 wells expected to be drilled in the current program year ending on June 30, 2027.

Black Stone’s agreement with Revenant Energy ("Revenant") covers 270,000 gross acres in which Black Stone currently controls approximately 122,000 undeveloped net acres, primarily located in Angelina, Nacogdoches, and San Augustine counties in Texas. The agreement includes minimum annual drilling commitments across three designated areas of interest ("AOIs"), measured by wells drilled in 2026 and completed gross lateral feet beginning in 2027. In September 2026, the Partnership entered into an amendment to the agreement that increased the overall 2027 drilling commitment by 7,000 gross lateral feet while extending until 2029 the requirement that a portion of the drilling commitment be completed in a second AOI. For 2026, Revenant is expected to meet its 4-well drilling commitment. As of the end of the third quarter, Revenant was operating one rig and had drilled 2 wells expected to turn to sales by year-end. Revenant spud the remaining 2 wells in early October 2026, with production expected in mid-2027.

In November 2025, the Partnership entered into a 220,000 gross acre development agreement with an affiliate of Caturus Energy, LLC ("Caturus") covering acreage primarily in Angelina, Cherokee, Houston, and Nacogdoches counties in Texas, which aims to push the Shelby Trough westward toward the Western Haynesville. Development activity under the original agreement is underway. Caturus drilled a pilot well in Cherokee County in the third quarter of 2026 and, in October 2026, spud its first 2 development wells, which are expected to begin production in the first half of 2027.

In October 2026, the Partnership entered into an amended and restated development agreement with Caturus that expands the contract area by 730,000 gross acres to a total of 950,000 gross acres and provides for incremental development commitments across two additional development areas primarily located in Houston, Trinity, and Polk counties in Texas. Consistent with the original agreement, minimum annual drilling commitments are measured in completed lateral feet net to Black Stone’s mineral ownership. The level of gross well activity associated with these commitments depends on well locations, lateral lengths, and Black Stone’s mineral ownership in the acreage developed. Each additional development area includes an initial pilot phase and a multi-year development program designed to ramp activity over time. Development activity in the first additional area is expected to begin with a pilot well by the first quarter of 2028 and, if Caturus elects to proceed following the pilot phase, would be followed by 2 gross wells in 2029 and a ramp to approximately 12 gross wells annually by 2034, as minimum annual drilling commitments increase from 8,000 to 33,600 net lateral feet over the same period. Caturus has the option to initiate development activity in the second additional area and, if elected, would begin with a pilot well by the end of 2031 and, if Caturus elects to proceed following the pilot phase, would be followed by 2 gross wells in 2033 and a ramp to approximately 12 gross wells annually by 2038, as minimum annual drilling commitments increase from 8,000 to 33,600 net lateral feet over the same period. The amended and restated agreement also provides Caturus flexibility to satisfy a portion of its annual development commitments for each development area through drilling in the other development areas, subject to certain minimum annual development requirements within each area.

In the Permian Basin, Blue Arrow Operating is progressing a 25 gross (1.9 net) well development on Black Stone’s acreage in the southern Delaware Basin. As of September 30, 2026, 10 gross (0.9 net) wells had been turned to sales, with the remaining wells expected to come online in the fourth quarter of 2026 and first half of 2027.

Acquisition Activity

The Partnership continues to acquire bolt-on acreage in multiple contractual development programs with significant inventory at high net interests across San Augustine, Nacogdoches, Angelina, Cherokee, Houston, and Trinity counties.

In the third quarter of 2026, consistent with the previously announced acquisition strategy, Black Stone acquired $14.6 million of additional (primarily non-producing) mineral and royalty interests. In October 2026, Black Stone acquired additional mineral and royalty interests and surface rights in the expanded Shelby Trough area from various sellers for $30.6 million in cash and $2.1 million in common units of the Partnership. The Partnership acquired the surface rights on a strategic tract to secure additional drilling locations in support of Black Stone's development agreements, and the acquisition included additional consideration tied to future production.

From September 2023 through October 2026, the Partnership completed $335.5 million of acquisitions, primarily consisting of mineral and royalty interests in the expanded Shelby Trough area. Black Stone’s commercial strategy going forward includes the continuation of meaningful, targeted mineral and royalty acquisitions to complement the Partnership's existing positions.

Hedge Position

Black Stone has commodity derivative contracts in place covering portions of its anticipated production for 2026, 2027, and 2028. The Partnership's hedge position as of October 30, 2026, is summarized in the following tables:

More detailed information about the Partnership's existing hedging program can be found in the Quarterly Report on Form 10-Q for the third quarter of 2026, which is expected to be filed on or around November 3, 2026.