Greenpeace is an organization that is very much concerned with protecting the environment and with promoting what it sees as social justice. Because of this, it is often very critical of large corporations. Large corporations are very much involved in global trade and with the World Trade Organization (WTO). For this reason, Greenpeace criticizes the WTO strongly.
Greenpeace feels that the WTO is controlled by the interests of big corporations. It believes that the big companies have an inordinate amount of power over what the major players in the WTO (such as the US and the EU) do. Because they have so much power, they force the EU to set up and enforce rules that are beneficial to them.
Because the WTO is dominated by the corporate interests, Greenpeace claims, it creates rules that help the big companies at the expense of the environment and/or the interests of poorer countries. Greenpeace worries, for example, that the WTO forces countries to accept the use of genetically modified crops. Greenpeace feels that these are bad for the environment. It worries that the WTO imposes rules that are good for the big countries and unjust to the less developed countries.
In these ways, Greenpeace feels that the WTO is in thrall to corporate interests and, therefore, that it does not do things that would promote environmentalism or social justice.