| Prefix | Block | Addresses | First registered | Organization |
|---|---|---|---|---|
| 70:B3:D5:36:3 | MA-S | 4.1 thousand | 4 Feb 2018 | Contec Americas Inc. |
| 70:B3:D5:39:2 | MA-S | 4.1 thousand | 10 Jan 2016 | Contec Americas Inc. |
| 70:B3:D5:8B:7 | MA-S | 4.1 thousand | 24 Dec 2017 | Contec Americas Inc. |
| 70:B3:D5:D1:0 | MA-S | 4.1 thousand | 9 Apr 2017 | Contec Americas Inc. |
Former Contec DTx MAC address blocks
The IEEE registry once carried 4 blocks registered to Contec DTx. All 4 blocks are now registered to Contec Americas Inc.. Contec Americas Inc. took over all of them.
Complete as of the current IEEE registry deploy. Dates are when each registration was first observed in public data, not legal assignment dates.