BEIJING, Oct. 19 -- A contractor who orders a Chinese-built tunnel boring machine for delivery after Nov. 18 will have to find out whether its country counts as "disputed" with Beijing, and the notice that raises the question never answers it.

The Ministry of Commerce and the General Administration of Customs published the rules on Monday as Announcements 50 and 51, alongside a separate drone notice co-signed by the Central Military Commission's Equipment Development Department. Xinhua's English report names tunnel boring machines and dredger items and gives the same Nov. 18 start.

The Chinese text sets two tiers. Exporters selling to "sensitive countries and regions that have disputes with China," in TEH's translation, must apply for a...