By Daniel Inman, Chao Deng and Shen Hong 

Shanghai is positioning itself at the forefront of China's campaign to reform state-owned enterprises by inviting private investment in the city's companies and encouraging stock-incentive plans for managers.

Improving the performance of the country's shambling state sector is a key goal for China's new leadership, which laid out its plans in a major blueprint last November. Shanghai was the first local government to release its reform guidelines late last year and the city has already seen a number of private-equity funds invest in its government-owned companies.

In the most recent high-profile deal, Shanghai Jin Jiang International Hotels (Group) Co. said last month that it received the city's approval to sell a 12.4% stake for 3 billion yuan ($488 million) to Chinese private-equity group Hony Capital Ltd. The hotel group is one of China's biggest and is set to operate a hotel in the country's tallest skyscraper when it opens next year in Shanghai's financial district.

As Shanghai sells stakes in its local enterprises, bigger deals are taking place on a national level. China Petroleum & Chemical Corp., or Sinopec, earlier this month said it would sell nearly 30% of its sales and marketing unit to 25 investors for $17.5 billion--a notable injection of private capital into China's largest oil refiner.

For Shanghai, the central government is looking for it to live up to its billing as a financial and commercial hub. The city is also developing a free-trade zone designed to drive a remaking of the country's financial system. Next month, a new program will link stock markets in Hong Kong and Shanghai, allowing international investors further access to China's largely closed off equities.

"Shanghai in many cases has led the economic experiments in China," said Tai Hui, chief market strategist for Asia at J.P. Morgan Asset Management. "So if SOEs are starting to partner with private equity, to me it sounds like it is going to be broadened out to the rest of the country."

Analysts say investment from private equity can improve the efficiency of state-owned companies because outside investors are more likely to make changes that will yield higher returns, and will be less influenced by government objectives such as high employment and steady economic growth. Still, because they have taken minority stakes private partners' influence on how a company is run will be limited.

Hony, which is also paying 1.8 billion yuan for a 10% stake in state-owned property developer and wastewater-management company Shanghai Chengtou Holding Co., has been working to restructure state assets since its founding more than a decade ago.

The firm is now doing "bigger, more significant deals" with state-owned enterprises, said Chief Executive John Zhao. With Jinjiang, he said, the priority will be helping the company put in place "market-driven governance" measures, including employee incentive programs.

There are other signs of change. Government-controlled Bright Food Group, which bought U.K. cereal maker Weetabix Food Co. two years ago, says half of its subsidiaries are now owned partly by private investors. In February, Hong Kong-based private-equity firm RRJ Capital said it will invest 1.5 billion yuan into Shanghai Bright Holstan, a dairy farming joint venture with Bright Dairy & Food, a subsidiary of Chinese conglomerate Bright Food Group.

Bright Food has also implemented a stock-incentive scheme in its subsidiaries that covers senior and mid-level management, and which is typically based on three-year performance targets.

Further deals could be slow in coming, though. Investors say Shanghai's state-owned enterprises are better run than their peers in other parts of the country. As a result, there is little need for external capital, leaving investment opportunities in the city hard to find. "The government officials are fairly capable," said Eric Xin, senior managing director of Citic Capital's private-equity arm in China. "There's not an incentive to sell off SOEs."

Signs of progress in Shanghai are significant because it is a hotbed of state-owned companies. Its state-owned assets account for 60.1% of gross domestic product, the second-most among China's provinces and municipalities, according to research from Credit Suisse. All but one of the city's 20 largest companies that are listed on the domestic stock market are controlled by the government, according to data from ChinaScope Financial.

The city's big state-owned companies include major industrial firms such as SAIC Motor Corp., China's largest auto group by sales, and Baoshan Iron & Steel Ltd., or Baosteel, one of the country's biggest steel producers. In August, a partnership was announced between Shanghai Baosteel Gases Ltd. and private-equity firm Warburg Pincus LLC to work together on industrial gas projects.

Write to Daniel Inman at daniel.inman@wsj.com, Chao Deng at Chao.Deng@wsj.com and Shen Hong at hong.shen@wsj.com

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