This excerpt taken from the VRSN 10-K filed Jul 12, 2007.
3.1.1 Add Grace Period
The Add Grace Period is a specified number of calendar days following the initial registration of a domain. The current value of the Add Grace Period for all registrars is five calendar days. If a Delete, Extend (RRP or EPP Renew command), or Transfer operation occurs within the five calendar days, the following rules apply:
Delete. If a domain is deleted within the Add Grace Period, the sponsoring Registrar at the time of the deletion is credited for the amount of the registration; provided, however, that Registry Operator shall have the right to charge Registrars a fee as may be set forth in its Registry-Registrar Agreement for disproportionate deletes during the Add Grace Period. The domain is deleted from the Registry database and is immediately available for registration by any Registrar. See Section 3.2 for a description of overlapping grace period exceptions.
Extend (RRP or EPP Renew command). If a domain is extended within the Add Grace Period, there is no credit for the add. The expiration date of the domain registration is extended by the number of years, up to a total of ten years, as specified by the registrars requested Extend operation.
Transfer (other than ICANN-approved bulk transfer). Transfers under Part A of the ICANN Policy on Transfer of Registrations between Registrars may not occur during the Add Grace Period or at any other time within the first 60 days after the initial registration. Enforcement is the responsibility of the Registrar sponsoring the domain name registration and is enforced by the SRS.
Bulk Transfer (with ICANN approval). Bulk transfers with ICANN approval may be made during the Add Grace Period according to the procedures in Part B of the ICANN Policy on Transfer of Registrations between Registrars. The expiration dates of transferred registrations are not affected. The losing Registrars account is charged for the initial add.