"Every move in my own home is monitored," said Yang Guoliang, a farmer from Jiangsu province, whose family faces constant surveillance due to their resistance against local land seizures. Their home is surrounded by cameras, and their communications and movements are tracked, often preempting their attempts to petition in Beijing.

The investigation, based on thousands of leaked documents, shows U.S. firms like Microsoft, Intel, IBM, Cisco, Oracle and others supplied critical technology for China's "Golden Shield" system, designed to censor and control dissent.