CALGARY, May 12 /CNW/ - Shell Canada Limited announced today that it has filed its formal offer to acquire all the common shares of BlackRock Ventures Inc. with securities regulators in Canada, and has mailed its offering circular and related documents to BlackRock shareholders. The offer remains open until 1:01 a.m. (Calgary time) on June 16, 2006, unless the offer is withdrawn or extended by Shell Canada. Under the terms of the offer, BlackRock shareholders will receive $24.00 for each BlackRock common share. The offer documents are available on www.sedar.com.