When sending in forms to the various governmental offices, from time to time we are suddenly requested to update a certificate. An example is a few years ago, a new law was passed necessitating certain health professionals to submit their certificate / license and obtain a new one.
When applying for the new certificate, many will advise you to just send it in and that it is not necessary to keep a copy.
TIP: Make a copy anyway. If you can have it notorised too, so much the better.
Recently there was a fire in the Misrad HaBriyut in Jerusalem and a number of files have been burned. In order to put files together, if yours was one of those burned, Misrad HaBriyut will ask you to submit a photocopy of all previous certificates. Having this copy will become invaluable to rememdy an unforeseen difficulty.