However it is also the case that VMware Fusion and Parallels have built-in support for OS X guests to make it much easier to install and setup an OS X guest it is therefore not necessary to make a special OS X iso image. While VMware Fusion and Parallels implement checks and will only allow an OS X guest if the host is a real Mac I don't believe VirtualBox does this. The same would apply to VMware Fusion and Parallels. Therefore yes it would be legal to run OS X in VirtualBox if VirtualBox is running on a Mac.

The “vInfo” tab displays for each virtual machine the virtual machine name, powerstate, template, SRM Placeholder, config status, DNS name, connection state, guest state, heartbeat, consolidation needed, power on date / time, suspend date / time, creation date / time, change version, number of cpu’s, latency-sensitivity, amount of memory, number of nics, number of virtual disks, total disk capacity, min Required EVC Mode Key, disk.EnableUUID, CBT, primary IP address, connected networks, number of monitors, video Ram KiB, resource pool, folder ID, folder name, vApp name, DAS protection, fault tolerance state, fault tolerance role, fault tolerance latency status, fault tolerance band width, fault tolerance secondary latency, provisioned storage, used storage, unshared storage, HA restart priority, HA isolation response, HA VM Monitoring, Cluster rule(s), Cluster rule name(s), install Boot Required, Boot delay, Boot retry delay, Boot retry enabled, Boot BIOS setup, Reboot Poweroff, EFI Secure boot, Firmware, HW version, HW upgrade status, HW upgrade policy, HW target, configuration path, log directory, snapshot directory, suspend directory, annotation, custom fields, datacenter name, cluster name, ESX host name, operating system name according to the config file, operating system name acoording to the VMware tools, virtual machine ID, VM SMBIOS UUID, VM UUID, VI SDK server type, VI SDK API version, virtual machine tags, VI SDK Server and VI SDK UUID.It is only legal to run OS X in a virtual machine if the host computer is a Mac.

Mac os x in vmware