Countervailing duty rules updated to tighten definitions, require exporting country consultations, and strengthen circumvention remedies. Amendments clarify that domestic producers are those whose collective output constitutes a major proportion of domestic production, excluding producers related to exporters or importers under a control test; add definitions for like article and period of investigation; prohibit publicising applications before initiation decisions and set bounds for investigation duration; require consultation with the exporting government before investigation; permit monitoring and onsite verification of undertakings and recommend provisional measures on violation; set a five year maximum for definitive duties with review and extension procedures; and create an anti circumvention framework allowing investigations, retrospective extension of duties, and reviews.