Here's what I did:

1. Installed the SATA hard disk in the enclosure
2. Connected it via USB
3. With Disk Utility I formatted the drive with an EXT4 file system
4. Started using the hard drive without any issue (copying and deleting files from it)

When I was doing a random `fdisk -l`, I noticed that the drive didn't have a valid partition table:

```
Disk /dev/sdc: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/sdc doesn't contain a valid partition table

```

Is it safe to keep using the drive like this? Should I be worried? :)

Thanks!