The commitment, made months before a high-stakes United Nations climate meeting in Paris, marks a 50-fold increase from a year ago when the Rockefeller family announced it was divesting from fossil fuels.
The study from consultancy Arabella Advisors found that 436 institutions and 2,040 people worth a total of USD 2.6 trillion have now pledged to get out of fossil fuels, either entirely or in particular sectors such as coal.
One of the latest, if least surprising, pledges came from the Leonardo DiCaprio Foundation, the environmental charity led by the actor and climate activist.
"Climate change is severely impacting the health of our planet and all of its inhabitants, and we must transition to a clean energy economy that does not rely on fossil fuels, the main driver of this global problem," DiCaprio said in a statement issued as he sat in the audience for the study's release in New York.
Fossil fuels -- especially coal, but to a lesser extent oil and gas -- contribute to emissions of carbon dioxide that have led to the planet's rising temperatures.
Scientists warn that, if left unchecked, global warming will seriously worsen droughts, floods and other disasters.