Referee's Signal Number 11 - Legal Touching
This signal is used by any official to indicate that a forward pass or scrimmage kick has been legally touched by a member of the defense/receiving team.
This means that the originally ineligible members of the passing/kicking team now may legally recover the ball or be downfield. It also means that certain other fouls such as pass or kick-catch interference no longer apply.
Begin the with one hand held high and pointing horizontally and sweep the other under the first hand creating a "T" shape. This may be repeated several times to give everyone a chance to notice it - do NOT blow your whistle.
You should also use the signal again once play has ceased to ensure that your fellow officials are aware of it. It is quite likely that a deep official will not have seen this and may have already dropped a flag for a interference call. Ensure that you become part of the conference with the Referee as this type of foul no longer applies and will need to be waved off (S13)