A signboard at the top of a staircase in the ageing Beijing offices of the National Development and Reform Commission (NDRC) directs lawyers and company officials to numbered conference rooms for antitrust meetings.
The printed list names half a dozen or more companies on any given day - a sign of the recent flurry of activity from the NDRC - one of China's three antitrust regulators. The direction of investigations has drawn heavy criticism from foreign officials and the overseas business community.
Inside those rooms, lawyers and executives describe meetings with the NDRC as "interrogations", where raised voices, flaring tempers and verbal reprimands are commonplace.
From interviews with more than two dozen attorneys, executives, and experts, who have been drawn into investigations with the NDRC's price supervision and anti-monopoly bureau, a picture emerges of a culture of intimidation under the leadership of Director General Xu Kunlin.
The agency's aggressive tactics coincide with an increasingly sobering business climate for foreign firms in China. Fears over the ruling Communist Party's support for domestic firms has prompted some to declare the end of a golden age for foreign business in the world's second-largest economy.
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The NDRC has investigated dozens of foreign firms over alleged "anti-competitive behavior" - from auto parts makers and milk powder producers to drugs firms and tech companies, including Qualcomm, which faces a potential record fine of more than $1 billion. Last week, the NDRC said it fined a Chinese venture of Volkswagen AG and Chrysler's local sales unit a combined $46 million, its first punishment of foreign carmakers for price-fixing.
Lawyers who have faced off against the NDRC say the antitrust bureau uses widespread behind-the-scenes tactics - from personal threats to forced apologies and brow beatings - to enforce China's 2008 Anti-Monopoly Law.
Xu, an outspoken official, denies his investigations are unfair or target foreign companies. His bureau's actions, however, are "reminiscent of Red Guard tactics," said a Chinese lawyer who represented a foreign firm in an NDRC probe.
"The lack of due process in these investigations is disturbing. It doesn't matter if this also is being done with Chinese companies. It doesn't matter if they bully their own people as well. The use of intimidation violates their own rules and cannot be one of its tools," said James Zimmerman, a Beijing-based partner at Sheppard Mullin, and a former chairman of the American Chamber of Commerce in China.