AMERICAN MEGATRENDS INC.

Any device whose MAC address begins with 00:40:D9 has a network interface built by AMERICAN MEGATRENDS INC.. This prefix (the OUI, or Organizationally Unique Identifier) is assigned by the IEEE and is the first three octets of the address.

OUI prefix

00:40:D9

Organization

AMERICAN MEGATRENDS INC.

Address

6145F N BELT PARKWAY NORCROSS GA US 30071

Source

IEEE OUI registry

Have a full MAC address? Look it up— we'll also tell you if it's a randomized (private) address rather than a real manufacturer prefix.