TRACKINGMCP · All container prefixes ↗
A container number beginning with CLAM is owned by Crowley, which operates under SCAC CMCU. You can track a CLAM container directly on Crowley. (Crowley SCAC)
| Prefix | CLAM |
|---|---|
| Owner | Crowley |
| Operating carrier | Crowley |
| SCAC | CMCU |
| Type | Carrier-owned |
Every shipping container carries an ISO 6346 number: four letters then seven digits (six serial + one check digit). The first three letters are the owner code and the fourth is always U for a freight container — so the four-letter prefix identifies who owns the box. Owner ≠ always the line carrying it: leasing companies own millions of boxes that sail under many carriers, which is why a leasing prefix is tracked by bill of lading, not by the prefix.
CLAM containers are owned by Crowley (SCAC CMCU).
Track a CLAM container by its number on Crowley — or use TrackingMCP's Crowley page.
Owner data from TrackingMCP's verified BIC prefix registry. Updated 2026-07-14.