“Viewers should disregard the TTG label ... when the label seems to have been attached by someone other than the photographer.”

Third-party image providers cannot credibly attach the TTG label to an unlabeled photo; only the photographer responsible for the photo can do that.

But when publishing an already-labeled photograph, image providers can credibly reproduce the TTG label if they also identify the photographer who is standing behind the Guarantee.

For more, see the guide to publishing TTG photographs