tpm_setownable reports the status of the TPM's flags regarding if the TPM can be owned. This is the default behavior and also accessible via the --status option. Requesting a report of this status prompts for the owner password. The --allow option sets the system's TPM to allow tpm_takeownership operations (via the TPM_SetOwnerInstall API). This operation requires physical presence. The --prevent option (via the TPM_SetOwnerInstall API) prevents the TPM from accepting tpm_takeownership operations. This operation requires physical presence. These operations are persistent. tpm_takeownership requires the tpm be enabled.
tpm_version(1) , tpm_takeownership(8) , tpm_setpresence(8) , tpm_setenable(8) , tcsd(8)