Suncor Energy extends Canadian Oil Sands Offer to January 8, 2016

CALGARY, ALBERTA–(Dec. 3, 2015) – Suncor Energy today announced it has extended its offer to Canadian Oil Sands Limited (“COS”) shareholders. Suncor will file a corresponding notice of extension to formally extend the expiry time of its offer to 6:00 p.m. MT (8:00 p.m. ET) on Friday, January 8, 2016.

“Our offer is full and fair and in the best interests of COS shareholders,” said Steve Williams, Suncor’s president and chief executive officer. “This process has always been about allowing COS shareholders to decide for themselves on the merits of our offer. The good news is that they will finally have their say.”

Since Suncor first expressed interest in acquiring COS, the oil market outlook has worsened, COS has reported negative free cash flow for the first nine months of 2015 and most recently announced an optimistic production outlook for 2016 that seems destined to continue COS’ track record of overpromising and under-delivering. Despite continuous claims and promises to the contrary, COS has failed to produce any viable alternative for its shareholders.

“The pressure is clearly on COS’ board and management to prove they are acting in someone’s interest other than their own,” said Williams. “The Alberta Securities Commission decision allows COS more time to surface a superior offer from a credible third party, something most analysts see as unlikely. They are now focused on a self-serving claim that COS, despite a balance sheet with a near junk credit profile, is better off as an independent company in a lower for longer crude oil price environment.”

Williams added, “Suncor’s offer delivers a significant and immediate premium, continued exposure to rising oil prices, and superior long-term upside versus the significant risk facing COS and its shareholders. We urge COS shareholders to act to protect the value of their investment by tendering their shares to the Suncor offer.”

About Suncor’s Offer to COS shareholders

Suncor is proposing to acquire all of the outstanding shares of COS. Under the terms of the offer, each COS shareholder will receive consideration of 0.25 of a Suncor share per COS share. Based on the closing price of Suncor’s shares on December 2, 2015, the offer represents an implied value of $9.19 per COS share or a significant 48% premium to the pre-offer trading price of $6.19 per COS share. All regulatory conditions to the offer, including those related to the Competition Act (Canada), have been satisfied.

In addition, COS shareholders will receive a 45% cash dividend increase. COS shareholders will also benefit from ongoing ownership in shares of Suncor, Canada’s leading integrated energy company. Suncor’s integrated business model and strong, investment grade balance sheet have consistently delivered superior returns to shareholders throughout the price cycle. Over the five years ending October 2, 2015, through changing oil price environments, Suncor has increased its dividend by 190% and delivered a total shareholder return of over 15%. During that same period, Canadian Oil Sands has cut its dividend by 90% and its shareholders have endured a negative total return of 69%.

Canadian Oil Sands shareholders are strongly encouraged to tender their shares to the Suncor offer to capture a significant, upfront premium and continued ownership in Suncor – a financially stronger, more diverse and more stable company.

For more information about Suncor’s Offer for COS, visit suncorofferforcanadianoilsands.com.

D.F. King has been retained as information agent for the offer. Any questions or requests for assistance in tendering COS shares should be directed to D.F. King at:

Toll Free in North America:

Banks, Brokers and Collect Calls: Toll Free Facsimile: 1-888-509-5907Email: inquiries@dfking.com

NT3