Struggling Chinese companies, some on the brink of delisting, are turning to the soaring property market to bolster their books.

At least 12 firms listed on mainland exchanges announced plans to sell real estate holdings in September amid a surge in property prices, according to Bloomberg calculations from stock exchange disclosures. Among them, seven suffered losses in the first half, while four have been placed on the exchanges' watch list for possibly being delisted. Most of them are in businesses unrelated to real estate.

"The companies faced earnings pressures in their core businesses, so they are looking to sell real estate in the high-price environment to airbrush the books and prevent a delisting scenario," Zhang Haidong, chief strategist at Jinkuang Investment Management in Shanghai, said by phone. "That's why investors need to be prudent when looking at the results, especially on taking out the non-recurring profits from the gains."

Runaway property prices are giving flailing companies a shot at survival amid uncertainty over China's growth and a volatile stock market. Under China's exchange rules, companies are warned with the possibility of delisting after two consecutive years of losses, and are suspended if they post a net loss in the following year.

Nanjing Putian Telecommunications Co, a loss-making telecommunication equipment manufacturer listed in Shenzhen, planned to sell two apartments in the heart of Beijing's school district to shore up its balance sheet, it said in filings last month. The value of the residences rose 16-fold since the firm bought them in 2004.

Shanghai Xinmei Real Estate Co, whose stock was halted from trading in Shanghai in April after it reported three straight years of losses, said in a statement on Sept 14 that it hoped to sell properties for at least 150 million yuan ($22 million) to "optimize its asset structure and resume trading as quickly as possible".

Weifang Yaxing Chemical Co, Xi'an Tian He Defense Technology Co, Shenzhen Shenbao Industrial Co and Shanghai Greencourt Investment Group Co are among the other companies with plans to sell real estate, filings show.

"Such sales won't change the long-term profits of these firms," said Ken Chen, a strategist at KGI Securities in Shanghai. "They're just buying more time to recover their business amid an economic turnaround."

Home prices in China surged by the most in six years in August, official data show. At least 21 cities have introduced purchase restrictions or toughened mortgage lending in the past month, reversing two years of easing to support home buyers.