On 18 June 2007, the Second Circuit Court of Appeals rejected a request by 16 American military veterans of the Vietnam War to overturn a previous decision refusing to recognise the liability of several companies that produced and sold Agent Orange. Used as a defoliant for military purposes during the Vietnam War, Agent Orange is a herbicide based on 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T). The production of 2,4,5-T also resulted in the presence, in residue form, of dioxin, a highly carcinogenic and teratogenic substance.

Between 1961 and 1971, the US government signed contracts with several American chemical companies for the production and sale of Agent Orange. The US military's defoliation campaign in Vietnam intensified with the conflict, and many of these contracts were subjected to government directives under the Defense Production Act (DPA) of 1950, which made the production and sale of Agent Orange an integral part of national military action.

The defoliation campaigns did not just affect local populations: members of the US army were also exposed to Agent Orange. The dioxins, which varied in quantity depending on the product's formulations, contaminated those exposed resulting in numerous and varied pathologies: cancers, miscarriages, congenital malformations and skin lesions.

In the United States, a compensation fund was set up to compensate veterans who had been exposed to Agent Orange. However, only those who came forward before 1994 were eligible for compensation. Because it is highly lipophilic, dioxin remains stored in human fat and is passed on from generation to generation, so that pathologies can develop long after an initial exposure.

In this case, the 16 veterans developed pathologies linked to their exposure to Agent Orange after the 1994 deadline. In 2004, the 16 appellants sought to hold the companies that produced and sold Agent Orange, including Dow Chemicals, liable on the grounds of manufacturing and design defects and negligence in warning of the product's toxicity. In response, the companies brought an application for summary judgment, asking the Court to declare the action inadmissible for lack of sufficient evidence to establish the facts.

On 9 February 2004, the District Court ruled in favor of the companies and granted the motion for summary judgment, dismissing the 16 veterans' claims. In its decision, the District Court noted that the Agent Orange companies had acted on the orders of the US Army. An initial appeal was lodged by the veterans on 3 November 2004, but was rejected on 16 November 2004 and again on 2 March 2005.

The decision of 18 June 2007 confirms the earlier decisions. In its ruling, the Court of Appeal noted that the composition, production and sale of Agent Orange had been approved by the US government, which had concluded that the product did not pose an "unacceptable health risk" in the context of the conflict. The companies had sufficiently informed the government of the possible risks of Agent Orange.