X0306 4 2019-08-20 0001362705 Sanchez Midstream Partners LP SNMP 0001656530 Stonepeak Catarina Holdings LLC 55 HUDSON YARDS 550 W. 34TH STREET, 48TH FLOOR NEW YORK NY 10001 true true See Remarks 0001656529 Stonepeak Catarina Upper Holdings LLC 55 HUDSON YARDS 550 W. 34TH STREET, 48TH FLOOR NEW YORK NY 10001 true true See Remarks 0001656528 Stonepeak Infrastructure Fund (Orion AIV) LP 55 HUDSON YARDS 550 W. 34TH STREET, 48TH FLOOR NEW YORK NY 10001 true true See Remarks 0001656527 Stonepeak Associates LLC 55 HUDSON YARDS 550 W. 34TH STREET, 48TH FLOOR NEW YORK NY 10001 true true See Remarks 0001656526 Stonepeak GP Holdings LP 55 HUDSON YARDS 550 W. 34TH STREET, 48TH FLOOR NEW YORK NY 10001 true true See Remarks 0001656525 Stonepeak GP Investors LLC 55 HUDSON YARDS 550 W. 34TH STREET, 48TH FLOOR NEW YORK NY 10001 true true See Remarks 0001656524 Stonepeak GP Investors Manager LLC 55 HUDSON YARDS 550 W. 34TH STREET, 48TH FLOOR NEW YORK NY 10001 true true See Remarks 0001550758 Dorrell Michael B. 55 HUDSON YARDS 550 W. 34TH STREET, 48TH FLOOR NEW YORK NY 10001 true true See Remarks 0001550764 Vichie Trent D 55 HUDSON YARDS 550 W. 34TH STREET, 48TH FLOOR NEW YORK NY 10001 true true See Remarks Class C Preferred Units 2019-08-20 4 A 0 939327 A 32250223 D These Class C Preferred Units of the Issuer (the "Class C Preferred Units") are payable by the Issuer on August 30, 2019, to Class C Preferred Unit holders of record on August 20, 2019, in satisfaction of the second quarter 2019 distribution on the Class C Preferred Units (as authorized on August 6, 2019 by the Board of Directors of the general partner of the Issuer). The Class C Preferred Units have the same voting rights as the holders of the Common Units but are not convertible into Common Units. These Class C Preferred Units are owned directly by Stonepeak Catarina Holdings LLC, and indirectly by Stonepeak Catarina Upper Holdings LLC, Stonepeak Infrastructure Fund (Orion AIV) LP, Stonepeak Associates LLC, Stonepeak GP Holdings LP, Stonepeak GP Investors LLC, Stonepeak GP Investors Manager LLC, Michael Dorrell and Trent Vichie. Stonepeak Catarina Upper Holdings LLC is the managing member of Stonepeak Catarina Holdings LLC. Stonepeak Infrastructure Fund (Orion AIV) LP is the managing member of Stonepeak Catarina Upper Holdings LLC. Stonepeak Associates LLC is the general partner of Stonepeak Infrastructure Fund (Orion AIV) LP. Stonepeak GP Holdings LP is the sole member of Stonepeak Associates LLC. Stonepeak GP Investors LLC is the general partner of Stonepeak GP Holdings LP. Stonepeak GP Investors Manager LLC is the managing member of Stonepeak GP Investors LLC. Each of Michael Dorrell and Trent Vichie serve as a managing member of Stonepeak GP Investors Manager LLC. Each Reporting Person disclaims beneficial ownership of the Class C Preferred Units except to the extent of his or its pecuniary interest therein, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of the Class C Preferred Units for purposes of Section 16 of the Exchange Act, or for any other purpose. /s/ Michael Dorrell 2019-08-27 /s/ Trent Vichie 2019-08-27