Oil tankers play a crucial role in global trade, but they also carry significant environmental risks. A single spill of crude or heavy fuel oil can devastate marine ecosystems, coastlines, and local economies. To address this, the international community developed the Civil Liability Convention (CLC), which requires tankers to carry a Civil Liability Certificate for Oil Pollution Damage (CLC Oil Certificate).
This blog explains everything about the CLC Oil Certificate—its background, requirements, validity, and importance—so seafarers, shipowners, and maritime professionals understand why it is one of the most important statutory certificates at sea.
What is the CLC Oil Certificate?
The CLC Oil Certificate is an official document issued by a ship’s flag state confirming that the vessel has valid insurance or financial security to cover liability for oil pollution damage caused by persistent oil cargoes.
Unlike the Bunker CLC Certificate, which applies to all ships above 1,000 GT for bunker fuel pollution, the CLC Oil Certificate applies specifically to oil tankers that transport persistent oil in bulk as cargo.
Legal Basis: Civil Liability Convention (CLC), 1969/1992 Protocol
The certificate is based on the:
International Convention on Civil Liability for Oil Pollution Damage, 1969 (CLC 1969)
Amended and strengthened by the 1992 Protocol (CLC 92)
Key points of the Convention:
Establishes strict liability on the shipowner for pollution damage.
Requires compulsory insurance to cover liability.
Provides a direct right of action for claimants against insurers.
Which Ships Require the CLC Oil Certificate?
All oil tankers carrying more than 2,000 tonnes of persistent oil in bulk as cargo.
Persistent oil includes:
Crude oil
Fuel oil
Heavy diesel oil
Lubricating oil
Who Issues the Certificate?
The Flag State Administration of the vessel issues the certificate.
Some flag states may authorize classification societies (ROs) to issue it on their behalf.
Ships registered in a state that has not ratified the CLC Convention may obtain the certificate from another contracting state, provided they trade in CLC waters.
Key Requirements for the Certificate
To obtain a CLC Oil Certificate, shipowners must demonstrate:
- Valid P&I Insurance – Usually provided by an International Group P&I Club.
- Ship Particulars – Name, IMO number, port of registry, tonnage, and cargo capacity.
- Owner’s Details – Registered owner’s full name and address.
- Adequate Financial Security – Coverage equal to the owner’s maximum liability under CLC.
Liability Limits under the CLC
The limits of liability depend on the gross tonnage (GT) of the tanker. For example (post-2012 amendments, rounded values):
Up to 5,000 GT → approx. 4.51 million SDR
Up to 140,000 GT → approx. 89.77 million SDR
Above 140,000 GT → max 89.77 million SDR
(SDR – Special Drawing Rights, an IMF unit of account)
Validity and Renewal
The certificate is valid for 12 months, linked to the insurance policy.
Must be renewed annually.
Ships without a valid certificate cannot trade in ports or EEZs of contracting states.
Importance of the CLC Oil Certificate
- Pollution Preparedness – Ensures financial resources are available for cleanup and compensation.
- International Compliance – Mandatory for trading in waters of CLC signatory states.
- Protection for Victims – Provides direct right of action against insurers.
- Smooth Operations – Prevents detentions and delays at port state control inspections.
- Reputation – Demonstrates commitment to responsible shipping practices.
Information Contained on a CLC Oil Certificate
Name and IMO number of the vessel
Port of registry and gross tonnage
Registered owner’s full name and address
Type of financial security (insurance or guarantee)
Name and address of insurer or guarantor
Validity dates
CLC Oil Certificate vs. Bunker CLC Certificate
Feature CLC Oil Certificate Bunker CLC Certificate
Applies to Oil tankers carrying >2,000 tonnes of persistent oil cargo All ships >1,000 GT
Based on CLC 1969/1992 Bunker Convention 2001
Pollution covered Oil cargo spillage Bunker fuel leakage
Victim rights Direct right of action against insurer Direct right of action against insurer
Conclusion
The CLC Oil Certificate is a cornerstone of maritime environmental regulation. It ensures that oil tanker operators take full responsibility for pollution risks and maintain adequate insurance to cover damages. Without it, a tanker cannot legally trade in most parts of the world.
Carrying this certificate onboard is not just a legal formality—it is a promise of accountability, environmental stewardship, and financial readiness in case of an oil pollution incident
