The broadcaster apologised for failing to warn viewers about flashing images in its a News at Ten report on the day of the royal wedding announcement, last November, which featured footage from the couple's photo call at St James's Palace.
Broadcast regulator Ofcom received a complaint from a viewer who has photosensitive epilepsy, who said that the report, which featured 13 seconds of flash photography, contained no warning before it was broadcast.
Television broadcasters are required to take precautions to maintain a low level of risk to viewers with epilepsy and only use flashing lights when editorially justified, preceded by a warning.
The BBC said its coverage in the Six O'Clock News came with a warning but "unfortunately this did not happen" with the repeat at 10pm, which was introduced by a reporter on location at Westminster Abbey.
The corporation said it "wishes to stress, however, that the fact of an oversight on this occasion should not be taken as evidence that it does not take this issue seriously" and the oversight "lay in this not being communicated to the reporter on location".
It said that, since the incident, news teams had been reminded of the importance of the rules.
Ofcom said it "acknowledges that the omission of a warning was as a result of human error on this occasion, and that the BBC news teams have taken additional compliance measures in response to this".
"However, the omission of a warning in circumstances where the BBC was aware the material was problematic is a matter of concern to Ofcom, and we do not expect a recurrence."
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