Seals are one of the most critical security measures in freight transportation. They establish — or fail to establish — that cargo arrived the way it left. Improper seal handling by brokers, shippers, receivers, and carriers creates serious vulnerabilities, leading to cargo theft, load tampering, and rejected insurance claims.
Many in the industry are failing to use seals properly:
- Some shipments have no seals at all, leaving cargo completely exposed.
- Some shippers apply seals randomly, without proper documentation or security checks.
- Some use cheap, low-quality seals that can be removed and replaced undetected.
- Some seals are not secured properly and fall off in transit, creating delays and disputes the carrier didn't earn.
Why seal numbers matter
Each security seal has a unique number. That number should be recorded on the Bill of Lading at the shipper. The BOL record is what makes the seal useful:
- The seal applied at the shipper must match the seal at the destination.
- A seal swap shows up as a number mismatch on the BOL — flagging tampering immediately.
- A broken or missing seal invalidates the shipment's integrity record and can lead to rejected deliveries and financial losses.
This post covers why seal mishandling is growing, what it actually costs, and how to enforce better seal security across your operation.
The most common seal mishandling failures
1. Not using high-security, tamper-resistant seals
Why it happens:
- Some shippers use low-quality plastic or cable seals instead of certified high-security seals.
- Carriers reuse old seals, making loads more vulnerable.
- Drivers replace seals without authorization, breaking the chain of custody silently.
Impact on brokers:
- Increased cargo theft and pilferage.
- Rejected insurance claims due to improper sealing.
- Loss of shipper trust over patterns of compromised loads.
How to prevent it:
- Require all shipments to use ISO 17712-certified high-security seals.
- Audit carrier seal handling procedures regularly.
- Train shippers on selecting and applying proper seals.
2. Shippers handing seals to drivers instead of applying them
Why it happens:
Some facilities hand seals to drivers instead of placing them on the trailer themselves. This allows unauthorized access to the load before transit even begins.
Impact on brokers:
- Cargo tampering goes unnoticed until delivery.
- Brokers bear the liability for stolen or damaged shipments.
- This single failure opens the door to a broad category of double-brokering activity, because the load becomes manipulable before it ever leaves the dock.
How to prevent it:
- Mandate shipper-applied seals in broker contracts, and strict verification at the receiver.
- Implement photographic or video evidence of seal application before departure and after arrival.
How brokers can improve seal security protocols
Four controls cover most of the exposure.
- Standardize seal requirements. Require ISO 17712-certified high-security seals on all loads.
- Make shipper-applied seals contractual. Drivers don't apply seals — staff at the shipping facility do, and the number goes onto the BOL immediately.
- Require photo and video verification. Carriers provide photo and video evidence during pickup and delivery showing the seal applied, intact, and matching the BOL.
- Educate carriers and shippers. Training on correct seal handling avoids the most common procedural mistakes.
Final thoughts
Seal mishandling is a preventable risk that continues to cause cargo losses, liability disputes, and rejected claims. Clear policies, real-time tracking, and shipper education are what move the needle.
If you want a Custom Seal Security Audit and training program for your team, that's part of our Supply Chain Security Assessment — we audit current handling, identify exposure, and write the SOPs you can hand to staff and contract carriers.