Oceana was established by a group of leading foundations — The Pew Charitable Trusts, Oak Foundation, Marisla Foundation (formerly Homeland Foundation), Sandler Foundation, and the Rockefeller Brothers Fund — after a 1999 study they commissioned discovered that less than 0.5 percent of all resources spent by environmental non-profit groups in the United States went to ocean advocacy.

No organization was working exclusively to protect and restore the oceans on a global scale. To fill the gap, their founders created Oceana: an international organization focused solely on oceans, dedicated to achieving measurable change by conducting specific, science-based policy campaigns with fixed deadlines and articulated goals.

The Ocean Law Project — also initiated by The Pew Charitable Trusts — was absorbed into Oceana in 2001 as Oceana’s legal arm. In 2002, Oceana merged with American Oceans Campaign, founded by actor and environmentalist Ted Danson, to more effectively address our common mission of protecting and restoring the world’s oceans.
Since its founding, Oceana has won more than 225 victories and protected more than 4.5 million square miles of ocean.