What an embargo is
An embargo is an agreed hold on publication: information or images are shared with selected people in advance, on the understanding that nothing may be made public until a set date and time. In film and TV publicity, embargoes let a production coordinate a release so that stills, announcements and coverage all land together rather than leaking out piecemeal.
For unit stills, the embargo period is the window in which images are circulated for review, selection and approval but are not yet cleared for publication. During this time the frames are sensitive: a leaked still from an unreleased title can undermine a carefully timed campaign.
Embargoes are why review copies are often protected. Sharing previews through secure, account-based access and adding watermarking to circulated copies keeps embargoed publicity stills marked and traceable until the hold lifts — at which point clean, approved files go out. For more, see our guide to watermarking production images.