The prop was accused of biting during the defeat by the Springboks in the second Test in Cape Town last Saturday. Sinckler denied the charge at a disciplinary hearing on Tuesday and the independent judicial committee found in his favour, clearing him of foul play.
The England player can now take his place on the bench for the decisive third Test this Saturday, also in Cape Town.
His case was heard by a three-man committee chaired by Australian special counsel Adam Casselden and including former Australian international players David Croft and John Langford.
A statement from World Rugby said: “British & Irish Lions player Kyle Sinckler appeared before an independent judicial committee via video link having been cited for an act of foul play contrary to Law 9.12 (biting) during the British & Irish Lions’ second test against South Africa on 31 July, 2021.
“The independent Disciplinary Committee chaired by Adam Casselden SC (Australia), joined by former international players David Croft and John Langford (both Australia), considered all the available evidence, including multiple broadcast angles, submissions from the player and his representative and expert witness testimony.
“The player denied that he had committed an act of foul play worthy of a red card. Having reviewed all the evidence, the committee deemed that on the balance of probabilities, it could not be satisfied that the player committed an act of foul play. On that basis, the committee dismissed the citing and the player is free to play again immediately.”