The US has launched an investigation into China’s intellectual property policies.
United States Trade Representative Robert Lighthizer said his office had “determined that these critical issues merit a thorough investigation”.
The move was expected after President Donald Trump asked Bob Lighthizer to review China’s practices.
China has voiced “serious concern” over the investigation, which could result in US trade sanctions.
The annual cost to the US economy from counterfeit goods, pirated software and theft of trade secrets has been estimated at up to $600 billion.
On August 18, the US announced it planned to look into hacking and reports that the Chinese government is steering investment into US companies in key industries as a way to gain access to new technology.
US officials will gather comments and hold a hearing in October as part of the so-called Section 301 investigation.
Penalties might be targeted against individual companies, or more wide-ranging, which will shape China’s reaction.
On August 15, China’s commerce ministry warned: “If the US side takes actions that impair the mutual trade relations, disregarding the facts and disrespecting multilateral trade rules, China will not sit idle.”