Four years ago, Canada’s government tried to keep state-owned companies out of Alberta’s oil sands. Now, they may be around for a while. ConocoPhillips, Marathon Oil Corp. and Royal Dutch Shell Plc decided this month to sell most of their oil sands to Cenovus Energy Inc. and Canadian Natural Resources Ltd. That leaves firms such as China’s Cnooc Ltd. among the last foreigners holding major stakes in the bitumen-soaked soil of northern Alberta. Chinese firms including Cnooc, PetroChina Co. Ltd. and China National Petroleum Corp. are now the second-largest foreign investors in the oil sands after U.S. companies. They may be willing to sell, but are hindered because their operations aren’t viewed as being as valuable as those sold recently, and the opportunity to sell may be closing as the pool of potential buyers shrinks, according to Mark Oberstoetter, lead analyst for upstream research at Wood Mackenzie Ltd. in Calgary. “We don’t think they will exit for a fire sale, and we are struggling to see who would step up and buy them,” said Oberstoetter. With the recent sales, Cnooc will become the fourth biggest producer by capacity in the oil sands behind Exxon Mobil Corp, Total SA and Devon Energy Corp. Paris-based Total, for one, has said it is seeking to sell more of its oil sands assets after selling 10 percent stake in the Fort Hills oil sands mine in 2015 to Suncor Energy Inc. International majors shed about $25 billion of their oil sands assets in the past year, shifting to more profitable resources elsewhere, such as U.S. shale. Oil sands crude is some of the world’s most expensive to produce, as it must be squeezed or steamed out of the ground and transported thousands of miles by pipeline or rail to refiners, most in the U.S. Following Cnooc’s $15.1 billion bid for Nexen Inc. in 2012, Prime Minister Stephen Harper approved the move while simultaneously announcing new takeover rules that prevent companies owned by foreign governments from buying controlling stakes in oil-sands businesses except under “exceptional circumstances.” State-run companies may have “larger purposes” that go beyond commercial objectives, Harper said at the time. Before Harper announced the restrictions, about $51 billion had flowed from such firms into the Canadian oil and gas industry over less than a decade. Prime Minister Justin Trudeau’s government hasn’t moved to loosen restrictions imposed by his predecessor, but has moved to deepen ties with China. John McCallum, a former federal lawmaker appointed by Trudeau as his ambassador to China, said the issue could come up should both countries launch formal free trade talks. Even when the rules were introduced, the need for them had decreased, said Oberstoetter. “We assumed that the Asians had gotten good footprints of assets in Canada and they wouldn’t do much more.” Different Goals Publicly-traded companies are driven by profitability and need to allocate capital accordingly, Dirk M. Lever, a Calgary-based analyst for Altacorp Capital Inc., said by phone Thursday. “Foreign governments may have other issues that are more pressing to their stakeholders, such as security of supply. They have a longer time horizon.” Cenovus’ Christina Lake and Foster Creek and the mining operations sold by Shell to Canadian Natural are larger and have more economies of scale than Nexen’s Long Lake and MacKay River, a PetroChina Co.-owned Brion Energy Corp. project. Nexen didn’t return an email seeking comment. Brion, which plans to begin oil production from MacKay River this summer, has made commitments to ship oil on Kinder Morgan Inc.’s expanded Trans Mountain pipeline, which is scheduled to start by the end of this decade, Brion spokeswoman Kristi Baron said by phone. PetroChina is “very much committed to our oil-sands project in Alberta,” she said. To be sure, one state-owned company did exit the oil sands recently. Statoil ASA, majority controlled by Norway’s Ministry of Petroleum and Energy, sold its operations to Athabasca Oil Corp. for C$825 million late last year. Fewer Buyers Whichever company seeks to leave, the opportunity to do so may be closing as the pool of potential buyers shrinks. Canadian Natural may have its ratings cut by Standard & Poor’s after the company agreed to acquire 70 percent of the Athabasca Oil Sands Project from Shell and Marathon last month for C$12.7 billion using about C$9 billion of debt, the rating agency said March 10. Suncor’s chief executive officer Steve Williams said in a February conference call that the “the window is starting to close” on opportunities for acquisitions after the company spent more than C$5 billion buying out Canadian Oil Sands Ltd. and Murphy Oil Corp.’s stakes in Syncrude Canada Ltd. “The logical thing is for Canadian Natural, Suncor Energy Inc. and Cenovus to digest these and restructure their balance sheets,” Oberstoetter said.