Pattern Energy Group Inc. and the Public Sector Pension Investment Board’s strategic initiatives

On June 19, 2017, Pattern Energy Group Inc. (PEGI), Pattern Energy Group LP (Pattern Development 1.0), Pattern Energy Group 2 LP (Pattern Development 2.0) and together with Pattern Development 1.0 (Pattern Development), Riverstone Holdings LLC and the Public Sector Pension Investment Board (PSP Investments) announced a series of strategic initiatives, including the following:

 The closing, on June 21, 2017, of the acquisition by PSP Investments from Pattern Development 1.0 of a 9.9 per-cent-interest in PEGI, making PSP Investments PEGI’s largest shareholder (PEGI Share Acquisition);

 The entering into of an agreement between PEGI and PSP Investments pursuant to which PSP Investments will co-invest with PEGI in various renewable energy projects (PEGI/PSP JVA);

 The acquisition by PEGI and PSP Investments of a 51-per-cent- and 49-per-cent-interest, respectively, in the 179 MW Meikle wind project in British Columbia and, effective as at the project’s commercial operations date, the 143 MW Mont Sainte-Marguerite wind project in Québec (Initial Project Acquisitions);

 The acquisition by PSP Investments of 49 per cent of the Class B interests held by PEGI in the Panhandle 2 wind project in Texas (Panhandle 2 Acquisition); and

 The indirect investment by PSP Investments in Pattern Development 2.0 (Pattern 2.0 Fund Investment).

PEGI is an independent power company, which is listed on the Nasdaq Global Select Market and Toronto Stock Exchange. It currently has a portfolio of 20 wind power facilities, including one project it has agreed to acquire, with a total owned interest of 2,736 MW in the United States, Canada and Chile. Pattern Development is a leader in developing renewable energy and transmission assets, having developed, financed and placed into operation more than 4.5 GW of wind and solar power projects.

PSP Investments is one of Canada’s largest pension investment managers with $135.6 billion of net assets under management as at March 31, 2017. It manages a diversified global portfolio composed of investments in public financial markets, private equity, real estate, infrastructure, natural resources and private debt.

PEGI and Pattern Development were represented on all aspects of the above transactions by an in-house team comprising Daniel Elkort, Executive Vice-President and General Counsel, and Dyann Blaine, Assistant General Counsel, Corporate and Vice-President.

For the PEGI Share Acquisition, Pattern Development 1.0 was also represented by Vinson & Elkins LLP with a team comprising Robert Seber, Jeffrey Shah, Syed Haq and Carter Olson; by Latham & Watkins LLP with a team comprising Barton Clark, Mathew Holt and Daniel Cote; and by Blake, Cassels & Graydon LLP’s Brendan Reay. PEGI was also represented by Davis Polk & Wardwell LLP with a team comprising John Butler and Abraham Einhorn.

For the PEGI/PSP JVA, PEGI was also represented by Davis Polk & Wardwell LLP with a team comprising John Butler, Abraham Einhorn and Robert Smith.

For the Initial Project Acquisitions, Pattern Development was also represented by Vinson & Elkins LLP with a team comprising Robert Seber, Jeffrey Shah and Syed Haq; and by Osler, Hoskin & Harcourt LLP with a team comprising John Groenewegen, Danna Donald and Michael Grantmyre. PEGI was advised by Davis Polk & Wardwell LLP with a team comprising John Butler and Abraham Einhorn.

For the Panhandle 2 Acquisition, Pattern Development 1.0 was advised by Orrick Herrington & Sutcliffe LLP with a team comprising Christopher Moore, Barbara de Marigny and Wolfram Pohl; and by Vinson & Elkins LLP on regulatory matters with a team comprising Billy Vigdor, Niel Imus and John Decker.

For the Pattern 2.0 Fund Investment, Pattern Development 1.0 was advised by Latham & Watkins LLP with a team comprising Barton Clark, Mathew Holt, Daniel Cote, Cheryl Coe and Valentin Riazanov.

PSP Investments was represented on all aspects of the above transactions by an in-house team comprising Mélanie Bernier, Vice President and Divisional General Counsel Legal Affairs, and Florence Simard (on secondment from Davies).

For the PEGI Share Acquisition, PSP Investments was also represented by Davies Ward Phillips & Vineberg LLP with a team comprising Franziska Ruf, Olivier Désilets, and Scott Fisher and Marc Berger.

For the PEGI/PSP JVA, the Initial Project Acquisitions and the Panhandle 2 Acquisition, PSP Investments was represented by Davies Ward Phillips & Vineberg LLP with a team comprising Nicholas Williams, Franziska Ruf, Brooke Jamison, Anthony Spadaro, Marc Pontone, Sarah Powell, Gabriella Lombardi, and Pawel Mielcarek and Jason Stapley.

PSP Investments was provided with tax advice on all aspects of the above transactions by Davies Ward Phillips & Vineberg LLP with a team comprising Peter Glicklich, Heath Martin and Marie-Emmanuelle Vaillancourt; regulatory advice was provided to PSP Investments by Linklaters with a team comprising Antonia Sherman, Sima Ostrovsky and Tara Rudra; and by Davies Ward Phillips & Vineberg LLP with a team comprising Charles Tingley and Alysha Manji-Knight.

For the Pattern 2.0 Fund Investment, PSP Investments was represented by Torys LLP with a team comprising Amy Johnson-Spina, Jay Romagnoli, and Batya Nadler and Steven Rotchtin.

For both the Panhandle 2 Acquisition and certain US regulatory matters, PSP Investments was also assisted by Andrews Kurth LLP with a team comprising Timothy Unger, Eric Markus, Stephanie Kroger, Geoffrey Walker and Kenneth Wiseman.

Lawyer(s)

John W. Groenewegen Danna Donald Franziska Ruf Olivier Désilets Nicholas C. Williams Brooke Jamison Sarah V. Powell Marie-Emmanuelle Vaillancourt

Firm(s)