August 3, 1994 – The Biodiversity Legal Foundation, later merged with the Center for Biological Diversity, and Predator Project submitted a petition to list American wolverines as a threatened or endangered species under the Endangered Species Act.
April 19, 1995 – The U.S. Fish and Wildlife Service found the 1994 petition to hold inadequate information to call for listing wolverines.
July 14, 2000 – The Biodiversity Legal Foundation (now the Center) and allies submitted another petition to the Service to list American wolverines as a threatened or endangered species under the Endangered Species Act.
October 21, 2003 – The Service published a 90-day petition finding announcing that the 2000 petition failed to present substantial information indicating that listing the wolverine was warranted.
June 8, 2005 – Conservation groups filed suit against the Service for using the wrong standards to assess their 2000 listing petition.
September 29, 2006 – A federal court in Montana ruled that the Service's 2003 decision not to list the wolverine was in error and ordered the agency to make a 12-month finding on the status of the wolverine.
April 18, 2007 – The Service obtained a five-month extension on the deadline for the court-ordered status review, which was moved to February 28, 2008.
June 5, 2007 – In response to the 2006 court order, the Service initiated a status review of the wolverine and opened a public comment period.
March 11, 2008 – In its 12-month finding, the Service announced that it would not protect the wolverine in the contiguous United States due to the fact that wolverines were not endangered in Canada. The Service determined that American wolverines did not constitute a “distinct population segment” and therefore did not warrant federal protection.
July 8, 2008 – The Center and nine other environmental groups, represented by Earthjustice, announced their intent to sue the Fish and Wildlife Service for its failure to list the American wolverine as threatened or endangered under the Endangered Species Act.
September 30, 2008 – The Center and its nine allies sued the U.S. Fish and Wildlife Service for its decision not to protect the wolverine despite the animal's imperilment and the ever-increasing threat of global warming.
June 10, 2009 – Under a legal settlement with the Center, the Service agreed to reconsider whether to add the wolverine in the lower 48 states to the endangered species list. A new listing determination was set to be due in December 2010.
December 13, 2010 – The Service found that endangered status for the wolverine was “warranted but precluded,” relegating the species to the candidate list to await Endangered Species Act protections indefinitely.
July 12, 2011 – The Center reached a landmark agreement with the Fish and Wildlife Service compelling the agency to move forward in the protection process for 757 species, including the American wolverine.
July 7, 2014 – According to a leaked memo obtained by the Center, scientists with the Service were ordered to reverse their own conclusions and withdraw the previous year's proposal to protect American wolverines under the Endangered Species Act.
August 12, 2014 – Despite severe threats from global warming, the Service reversed the conclusions of its own scientists and withdrew its proposal to protect American wolverines under the Endangered Species Act in the lower 48 states.