The ad, for the 12A-rated thriller, appeared before an animated clip on the video-sharing site called 'The Duck Song'.
It included action sequences involving shooting, vehicle chases and punching, with the voiceover stating: "An assassin wants him dead", which also appeared as text on the screen.
The complainant challenged whether the ad was irresponsible because it had appeared next to a clip for children.
In its defence, Lions Gate said it expected the ad to be seen by over-13-year-olds, after its scheduling had been approved by YouTube, and the online ad was the same as the one cleared by Clearcast for TV.
YouTube could not verify if the clip had appeared before 'The Duck Song' and said it must have appeared on a partner page. If it had been viewed on its site, the viewer would have been presented with a warning for under-13-year-olds.
It said it considered the ad to be "family safe" because although the scenes were cut quickly and much of the filming was dark and suggestive, there was no explicit violence, no blood or scenes of death, no shooting victims and no adult language or explicit sexual content.
The ASA said the sounds of shooting, explosions and punching were unsuitable for younger children. It noted YouTube users had to be 13 years old to create an account, but content was viewable to all internet users, whether they were logged in or not.
It ruled the ad must not appear again in its current form. It told Lions Gate that it must make sure future marketing communications addressed to, targeted directly at, or featuring children, contained nothing that was likely to result in their physical, mental or moral harm.
Yesterday, Lions Gate partnered with Facebook to become the first film studio to launch a film to rent on the social network the same day it goes on sale - coincidentally the film was – 'Abduction'.
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