An example tape storage drive may include reading/writing circuitry and control circuitry. The reading/writing circuitry may be to read from and write to tape media of tape cartridges. The processing circuitry may be to, in response to a tape cartridge being loaded into the tape storage drive, validate initialization of the tape cartridge. The processing circuitry may be to, in validating initialization of the tape cartridge, determine whether a tape format portion of a cartridge memory of the tape cartridge contains tape format data and whether the tape format portion is write-locked. If the tape format portion contains tape format data and is not write-locked, then the processing circuitry may fully initialize the tape cartridge including selecting a tape format for the tape cartridge and updating the tape format data to specify the selected tape format, write-lock the tape format portion, and then deem initialization of the tape cartridge to be complete.