Your Data Release Number (DRN) is a four-digit number assigned to your application by Federal Student Aid. Both the electronic and paper Student Aid Report (SAR) have the DRN in the upper right corner. You will need the DRN if you contact the Federal Student Aid Information Center to make corrections to your mailing address or the schools you listed on your FAFSA. The DRN also allows you to release your FAFSA data to schools you did not list on your original FAFSA.
The answer to your question is here: http://www.fafsa.ed.gov/faq010.htm#faq010_3QuoteYour Data Release Number (DRN) is a four-digit number assigned to your application by Federal Student Aid. Both the electronic and paper Student Aid Report (SAR) have the DRN in the upper right corner. You will need the DRN if you contact the Federal Student Aid Information Center to make corrections to your mailing address or the schools you listed on your FAFSA. The DRN also allows you to release your FAFSA data to schools you did not list on your original FAFSA. While the FAFSA has various issues, the website is pretty good about describing the actual form itself.