Citation: http://mobile.railwaygazette.com/index.php/news/news/profile/20463
Some metro lines in China are supported by Hong Kong MTR on construction technology or operation. I don't know why such aids are necessary for those lines.
When Beijing inaugurated subway lines in 1960s, authoriqties didn't get support from Hong Kong MTR. But, in 2000s, Beijing, Shanghai, and Shenzhen adopted MTR as a supporting company.
