The International Court of Justice (ICJ) judgment in Whaling in the Antarctic, a dispute brought by Australia against Japan, found that Japan had violated the International Convention for the Regulation of Whaling (ICRW) moratoria on all commercial whaling and the use of factory ships to process whales, and also the prohibition on whaling in the Southern Ocean Sanctuary. In the course of analyzing whether special permits issued by Japan qualified for the scientific whaling exemption under Article VIII ICRW, the Court benefited from a more robust scientific fact-finding process than at times in the past. The judgment emphasized the mutual obligations of this multilateral agreement by taking the view that the provisions of the ICRW’s scientific whaling exemptions are neither self-judging nor subject to a ‘margin of appreciation’ in favour of a state party claiming the exemption. The case was driven by conflicting attitudes towards commercial whaling, and also towards global common spaces. The ICJ’s decision and Japan’s response indicate the limits of the ICRW in resolving those differences.