A Shanghai court has fined three local tech firms for helping spread rumours about KFC fast food chain that included doctored photos of deformed chickens and allegations the birds had six wings and eight legs.

In a statement, the Xuhui District People's Court said Yingchenanzhi Success and Culture Communication, Taiyuan Zero Point Technology and Shanxi Weilukuang Technology had "damaged KFC's reputation" and "caused it economic losses" by permitting the allegations to be posted on their social messaging accounts.

KFC has been battling food safety allegations in China for several years. Credit:Qilai Shen

The companies were ordered to make an official apology and fined a combined 600,000 yuan, an amount that fell far short of the 1.5 million yuan that KFC owner Yum Brands had asked each company to pay in damages.

"We brought suit against these individuals for making false statements about the quality of our food and we are pleased with the outcome," China-based Yum spokeswoman Cindy Wei said.