Model and property releases
Who signs one, what it covers, and where to find it on an image.
A release is written permission from a recognisable person, or the owner of private property, allowing the picture to be used commercially.
Every image page shows its status under Released. "Model &/or property release on file" means the contributor has supplied one and the image can be used in advertising.
If you are a contributor, you upload releases against the asset in your studio. An image of a recognisable person without one can still be published, but it will be marked Editorial and will earn less, because most commercial buyers cannot use it.