A juvenile strike can be sealed from public access, but it still counts as a strike if you commit a felony in the future. If you commit a felony after your strike is sealed, the law allows the District Attorney, the court, and the Probation Department to access the sealed strike for the purpose of initiating criminal charges for the subsequent felony, to determine whether you should be transferred to adult court, to determine the appropriate consequences of the subsequent felony, and to prove the existence of the prior strike to enhance the sentence on the subsequent felony.  The only way to avoid future strike consequences is to convince the juvenile court judge to either dismiss the strike or to reduce it to a misdemeanor before sealing it. Once a strike is dismissed or reduced to a misdemeanor, it no longer counts as a strike.