Suncor Energy Inc. (NYSE: SU) said Feb. 5 it has acquired a roughly 70% stake in Canadian Oil Sands Ltd.

About 72.9% of Canadian Oil Sands shares equating to nearly 353.3 million common shares and accompanying rights have been tendered to Suncor's offer, according to a release.

Suncor will take up all tendered shares and those shares will be paid for in accordance with the terms of the offer, initially made Oct. 5 and most recently amended Jan. 22.

In January, Suncor reached a deal to acquire rival Canadian Oil Sands by raising its all-stock offer. The deal, valued at about C$4.24 billion (US$2.93 billion), came days after Suncor's hostile bid fell short of support from Canadian Oil Sands shareholders.

Suncor will now offer Canadian Oil Sands shareholders 0.28 of a Suncor share for each share held, up from the initial bid of 0.25 shares. The new offer values Canadian Oil Sands at C$8.74 per share, a premium of nearly 17% over the closing price of both stocks on Jan. 15.

Suncor has extended its offer to Feb. 22 so that Canadian Oil Sands shareholders who have not yet tendered their shares can do so. Further extensions beyond Feb. 22 are not anticipated, the release said.

D.F. King is information agent for the offer.

Related: Suncor To Buy Canadian Oil Sands With Sweetened Offer