I am a Laser sailor looking to move up into a J24 and have been looking at a few used boats. Can anyone explain the rules regarding the Measurement Certificate? Specifically, does a boat I purchase need to have one? If I purchase a J24 with a certificate; do I have to update it; i.e. have it 'measured' again? One of the boats I am looking at has the certificate dated 9 years ago/2 owners ago; is this still valid if the current owner has not updated the certificate? The Measurement Form, Preamble #5 states "change of ownership invalidates the certificate; if the current owner did not update the certificate, how difficult is it for me to update and obtain a current one? Thanks for any help!