noun
illegal price-fixing agreement
Refers to a secret, often cartel-like agreement to fix prices, typically in violation of antitrust or competition laws.
その業界では闇価格協定が結ばれていたと報じられた。
It was reported that an illegal price-fixing agreement had been made in that industry.
Compound of 闇 (yami, 'darkness; illegal') + 価格 (kakaku, 'price') + 協定 (kyōtei, 'agreement'). The exact historical derivation is uncertain; the term likely emerged in economic or legal discourse.