Patent ID: 8400895

Claim:
A rewritable information recording medium on which a read/write operation is performed on a block-by-block basis, the information recording medium comprising: a user data area to store user data written thereon; a spare area including a replacement block that would replace a defective block in the user data area; and a defect management information area to store defect management information for use to manage the defective block in the user data area or the spare area, wherein the spare area is used sequentially in a predetermined direction, and wherein the defect management information includes: a spare defect attribute indicating the defective block, if any, in the spare area; a defect entry specifying the sector address of the defective block; and next available spare location information for use to manage a location in the spare area from which a next replacement block is available, and wherein the spare defect attribute includes at least one of: a definite spare defect attribute indicating that the defective block in the spare area is definitely unusable; and a provisional spare defect attribute indicating that the defective block in the spare area used to be a defective one but may have had its defect repaired by now.