Transformers 4
Transformers 4 is being sued for not fulfilling 'contractual obligations'.Paramount Pictures

Hollywood blockbuster Transformers 4: Age of Extinction, which set a record for its massive box office returns, has landed in a credit controversy.

Officials at China's Wulong Scenic Area have reportedly sued the producers for not fulfilling specific contractual obligations.

Permission to shoot at the location was given on the condition that the words 'China Wulong' would be prominently displayed in the movie. But it was missing in the opening and ending credits in the film, reported a Chinese website CCTV.com.

Wulong signed a contract with Transformers 4 last October in exchange for using the Unesco World Heritage site as a shooting location for five days, and received a hefty product-placement fee. The producers promised to use the words 'China Wulong' in the movie, which they didn't follow through.

The Wulong Karst Tourism company general manager Huang Daosheng said, "The story was set near Hong Kong. People that don't know us will think Wulong is adjacent to Hong Kong. It's misleading to tourists and audiences. The effect can be long-lasting."

The authorities believe that this could also discourage future tourists from visiting the location.

Mis-read sign

The Chinese company that co-produced Transformers 4 claims that the omission was simply a mistake made by foreigners who do not know Mandarin, and who thought a stone tablet that reads 'Qinglong Bridge' meant 'China Wulong.'

The head of 1905 Internet Technology company Liang Longfei said, "I e-mailed Paramount as soon as possible. Paramount said their production company ILM did get the instruction, but maybe made a mistake. The staff don't know Chinese."

"But when I watched the movie premiere in Hong Kong with my American partner Mark, he said look, the 'China Wulong' stone tablet is really good," Liang continued. "I double-checked with him, and said do you mean these three characters? He said 'Yes, isn't this 'China Wulong'?' I said 'No.' It's a language problem."

In the lawsuit filed at a court in Chongqing, officials demand that Wulong be properly credited in the movie's DVDs and all other versions.

Transformers 4: Age of Extinction is directed by Michael Bay and stars Michael Wahlberg, Jack Reynor, Nicola Peltz and Stanley Tucci.