What causes an MC application to fail?
The four most common failure modes: legal-name mismatches between the USDOT and the OP-1, incomplete OP-1 forms (missing tariff or HHG arbitration sections), missing BOC-3 or insurance filings during the 21-day window, and unresolved public protests during the protest window.
Legal-name mismatch is the single most common rejection. The OP-1 has to match the USDOT exactly — same LLC name, same address, same EIN. A carrier who set up a USDOT under a personal name and later formed an LLC has to update the USDOT first before applying for the MC.
Incomplete OP-1 trips up applicants who skip the tariff section (required for property carriers), the HHG arbitration section (required for household-goods movers), or the broker bond confirmation (required for brokers).
The 21-day window is when the BOC-3 + insurance need to land. The FMCSA reviews on day 22; if either is missing, the authority does not activate — the application doesn't fail outright, but authority sits in PENDING until the missing items are filed.
Public protests are rare but block activation when they happen. A protest typically comes from a competitor or a creditor with standing; resolving it requires either withdrawal of the protest or a hearing before the authority can activate.