Several Huawei Technologies employees have collaborated on research projects with Chinese armed forces personnel, indicating closer ties to the country’s military than previously acknowledged by the smartphone and networking powerhouse.

Over the past decade, Huawei workers have teamed with members of various organs of the People’s Liberation Army on at least 10 research endeavours spanning artificial intelligence to radio communications.

They include a joint effort with the investigative branch of the Central Military Commission — the armed forces’ supreme body — to extract and classify emotions in online video comments, and an initiative with the elite National University of Defense Technology to explore ways of collecting and analysing satellite images and geographical coordinates.

Those projects are just a few of the publicly disclosed studies that shed light on how staff at China’s largest technology company teamed with the People’s Liberation Army on research into an array of potential military and security applications.

Bloomberg culled papers from published periodicals and online research databases used mainly by Chinese academics and industry specialists. The authors of the treatises, which haven’t been reported in the media previously, identified themselves as Huawei employees and the company name was prominently listed at the top of the papers. “Huawei is not aware of its employees publishing research papers in their individual capacity,” spokesman Glenn Schloss said in a messaged statement. “Huawei does not have any R&D collaboration or partnerships with the PLA-affiliated institutions,” he said. “Huawei only develops and produces communications products that conform to civil standards worldwide, and does not customise R&D products for the military.”

China’s defence ministry didn’t respond to a faxed request for comment. Huawei Chief Legal Officer Song Liuping on Thursday reaffirmed the spokesman’s comments. “Huawei doesn’t customise products nor provide research for the military,” he told reporters . “We are not aware of the papers some employees have published. We don’t have such joint-research projects” with the PLA.

The Trump administration has imposed strict limits on Huawei’s ability to do business with US companies and urged allies to follow suit, saying it poses a national security threat. Washington has zeroed in on what it says is Huawei’s close association with the armed forces in part because billionaire founder Ren Zhengfei — a self-avowed Party loyalist — was an officer who worked on communications during his military tenure.

It’s unclear whether the studies Bloomberg saw encompassed every instance of Huawei-employee collaboration with the PLA. Many sensitive projects are classified or just never make it online. While researchers with both Huawei and the military published thousands of papers according to that database, only the 10 Bloomberg saw were joint efforts. And the company employs upwards of 180,000 people.

The research papers show one area of overlap, at least in terms of personnel. While they don’t prove Huawei itself has close links to the Chinese military, they do show that the company’s relationship — or at least of its employees — with the PLA is more nuanced than its executives have outlined publicly.

Huawei has said it never discloses sensitive information to the government and wouldn’t even if asked. Ren himself has shrugged off Huawei’s relationship with the military since he emerged from semi-seclusion in January to speak with foreign media for the first time in years.

“We have no cooperation with the military on research,” Ren had said, according to a transcript Huawei provided. “Perhaps we sell them a small amount of civilian equipment. Just how much, I’m not clear on because we don’t regard them as a core customer.”

The armed forces too have strongly denied official links to Huawei. “Huawei is not a military company,” Defense Minister General Wei Fenghe said at the Shangri-La Dialogue in Singapore in June. “Do not think that because the head of Huawei used to serve in the military, then the company that he built is part of the military.”

Bloomberg was unable to contact the employees listed or determine whether they remain at the company.

Wong Kam Fai, a Chinese University of Hong Kong professor, said that it’s common that universities in China and companies would collaborate with the government or military. Chinese “universities are quite open to working with the military. If it’s very sensitive, it will be classified.”

Wong said the papers on using technology to detect emotions in videos weren’t particularly cutting edge, which partly explains why they can be made public. “Different projects have different sensitivity levels and sometimes the government will own the IP,” he added. “It’s possible that there’s a lot of research that people are just not seeing, because some military research is sensitive and classified.”

In addition, researchers sometimes put their employer’s name on papers without notifying the company, or wait till the paper comes out before doing. That’s because there’s a good chance some papers may never get published.

“In the US they have similar arrangements as well. The US has military grants,” Wong said. “There are many sources of funding, including from the military for research.”

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