Dematerialization is the process of altering securities held in physical form into holdings in book-entry (electronic) form.
In Demat form, one investor's shares are not well-known from another investor’s shares, and these shares do not have any unique number, folio number, or certificate number.
SEBI’s policy requires a company making a public issue of shares to agree with all the depositories to dematerialize its shares so that investors can be given the choice of holding the shares in dematerialized form.
Rematerialization is overturned of dematerialization and is the process of changing securities held in electronic form into physical form.
Upon investors' request, Securities on rematerialization are fixed in physical form with unique numbers, in place of the securities held electronically in book-entry form with a depository.