An optical data storage medium (1) comprising a dye-based recording layer is described. It has substantially parallel tracks for recording user information in a pattern of optically detectable marks, the tracks being provided with a guide groove, the groove being present in a user data area (3) and in an information area (2) and being trackable by a focused radiation beam (7) with the push pull method. The value of the normalized push pull signal (PPN) in the unrecorded information area is PPN-i and the value of PPN in the unrecorded user data area is PPN-u and PPN-i is lower than PPN-u. It is achieved that the information area of such an optical data storage may be read by a legacy optical data drive without causing damage to the drive. Further an apparatus for reading and a corresponding method are described.