National Grid PLC — Director's Dealing 2015

Oct 9, 2015

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: Dominion Midstream Partners, LP (DM)
CIK: 0001603286
Period of Report: 2015-09-29

Reporting Person: NATIONAL GRID PLC (10% Owner)

Holdings (Non-Derivative)

Security	Shares	Ownership
COMMON UNITS	6783373	Indirect

Footnotes

F1: North East Transmission Co., Inc. is the beneficial owner of 6,450,854 Common Units and National Grid plc is the ultimate parent of North East Transmission Co., Inc. through its subsidiaries National Grid (US) Holdings Limited, National Grid (US) Investments 4 Limited, National Grid (US) Partner 1 Limited, National Grid North America Inc., National Grid USA, KeySpan Corporation, KeySpan Energy Corporation and The Brooklyn Union Gas Company.

F2: National Grid IGTS Corp. is the beneficial owner of 332,519 Common Units and National Grid plc is the ultimate parent of National Grid IGTS Corp. through its subsidiaries National Grid (US) Holdings Limited, National Grid (US) Investments 4 Limited, National Grid (US) Partner 1 Limited, National Grid North America Inc., National Grid USA, KeySpan Corporation, KeySpan Energy Corporation and National Grid Development Holdings Corp.