The term:
Shadow Fleet
or:
Dark Fleet
has become increasingly common in international shipping.
It generally refers to vessels operating with unusually low transparency, often involving complex ownership structures, frequent flag changes, AIS manipulation, questionable insurance arrangements and ship-to-ship cargo transfers.
Many of these vessels have been associated with oil trades involving sanctioned countries such as Russia, Iran and Venezuela.
However, sanctions evasion is only part of the concern.
Ageing vessels, uncertain insurance and limited regulatory oversight can also create serious maritime safety and environmental risks.
What Is the Shadow Fleet?
“Shadow Fleet” is not the name of a single shipping company or organised fleet.
It is a general term used by regulators, insurers and maritime analysts to describe vessels displaying characteristics associated with opaque or high-risk shipping activity.
Common characteristics may include:
- Complex ownership structures
- Shell companies
- Frequent flag changes
- Weakly regulated flag registries
- Unclear insurance
- AIS manipulation
- Ship-to-ship transfers
- Participation in sanctioned oil trades
The International Maritime Organization has previously raised concerns regarding ageing vessels, poor maintenance, unclear ownership and inadequate insurance within the dark fleet.
How Large Is the Shadow Fleet?
The fleet has expanded significantly since 2022, particularly as sanctions and price-cap restrictions changed the way Russian and other sanctioned oil was transported.
However, estimates vary because different organisations use different definitions.
Kpler estimated that approximately 3,300 vessels were operating within global shadow networks by the end of 2025.
S&P Global used a narrower tanker-focused methodology and identified approximately 978 tankers, representing around 18.5% of global oil tanker capacity.
Different fleet estimates therefore do not necessarily contradict each other.
They may simply reflect different definitions of what qualifies as a shadow vessel.
Why Is the Shadow Fleet Considered Dangerous?
One major concern is vessel condition.
Established commercial shipping companies normally operate under structured maintenance, inspection and insurance requirements.
Some shadow tankers, however, are older vessels with less transparent maintenance, classification and insurance arrangements.
Age alone does not automatically make a ship unsafe.
The greater concern is the combination of:
Ageing vessels
Unclear maintenance
Weak insurance
Opaque ownership
Higher-risk operating practices
For tankers carrying large quantities of crude oil, a collision, grounding or structural failure could create significant environmental consequences.
What Is AIS and Why Do Ships “Go Dark”?
AIS stands for:
Automatic Identification System.
Ships normally use AIS to broadcast information such as:
- Identity
- Position
- Course
- Speed
This helps other vessels and maritime authorities understand surrounding traffic.
Some high-risk vessels may:
- Switch off AIS
- Disappear from tracking for extended periods
- Broadcast false locations
- Manipulate vessel identity
- The intentional transmission of false AIS information is commonly referred to as:
AIS Spoofing.
When digital vessel information cannot be trusted, it becomes more difficult for authorities and other ships to understand actual maritime traffic.
Why Is AIS Alone No Longer Enough?
AIS remains an important maritime safety system, but it depends on ships transmitting accurate information.
When AIS is switched off or manipulated, additional monitoring methods may be required.
Modern maritime intelligence increasingly combines:
- Satellite imagery
- Synthetic Aperture Radar
- Optical imagery
- Radio-frequency detection
- Historical vessel movements
- AI-based behaviour analysis
Comparing digital vessel signals with independent physical observations can help identify ships even when they attempt to hide their movements.
Why Does Insurance Matter?
Commercial vessels normally carry insurance designed to cover major maritime liabilities, including accidents and pollution.
Some shadow vessels may instead rely on:
- Non-mainstream insurers
- Self-insurance arrangements
- Difficult-to-verify cover
- or inadequate liability protection.
This creates an important question after a serious accident:
Who pays?
If a tanker causes a major oil spill while the beneficial owner and insurer are difficult to identify, compensation and cleanup claims may become significantly more complicated.
What Are Ship-to-Ship Transfers?
A:
Ship-to-Ship Transfer
or:
STS Transfer
occurs when cargo is transferred directly between two vessels at sea.
STS transfers are not inherently illegal and are used legitimately in commercial shipping.
However, some shadow fleet operations combine STS transfers with:
- AIS manipulation
- Frequent flag changes
- Opaque ownership
- Complex cargo movements
This can make the true origin and transport chain of oil more difficult to trace.
Poorly controlled offshore transfers involving ageing tankers may also create additional environmental risks.
What About the Human Cost?
Shadow fleet activity can also affect seafarers.
Seafarer abandonment reached record levels in 2025.
According to ITF and Lloyd’s List Intelligence data, 27 of 46 abandonment cases involving larger tankers and LPG carriers were associated with vessels on shadow fleet watchlists.
That represented approximately 66% of those cases.
Across the wider shipping industry, 6,223 seafarers were abandoned on 410 vessels during 2025.
Abandonment can involve unpaid wages, lack of basic support and shipowners failing to provide repatriation.
Opaque corporate ownership can make it even more difficult to identify who is ultimately responsible.
How Are Governments Responding?
Authorities in Europe, the United States and other jurisdictions have increased action against shadow fleet vessels and the networks supporting them.
European countries have increased attention on:
- Valid vessel registration
- Insurance documentation
- Safety certificates
- False flags
- Maritime services
European governments have also coordinated action against stateless and falsely flagged vessels in the Baltic and North Seas.
The European Union continues to expand sanctions affecting shadow fleet vessels.
By April 2026, 632 vessels were subject to EU port-access and maritime-service restrictions.
A further 41 vessels were added in July, while restrictions were also expanded to parts of the support network.
Enforcement is increasingly moving beyond individual tankers to include:
- Owners
- Managers
- Insurers
- Traders
- Service vessels
- Bunkering providers
- Crewing and other facilitators
Why Does the Shadow Fleet Matter to Normal International Trade?
Most legitimate commercial cargo is not transported through shadow fleet operations.
However, the wider shipping market can still be affected.
Potential impacts include:
- Maritime accidents disrupting shipping lanes
- Additional port inspections
- Changing sanctions lists
- Higher insurance costs in high-risk regions
- Carrier route changes
- Changes to port calls
For normal importers and exporters, the practical priority is not to personally determine whether a vessel is a “ghost ship.”
Instead, businesses should work with transparent carriers and logistics providers using vessels with:
- Valid registration
- Recognised safety oversight
- Reliable insurance
- Transparent routing
- Appropriate sanctions compliance
Why Is Maritime Compliance Becoming More Important?
Freight decisions have traditionally focused on:
- Price
- Transit time
- Sailing schedule
- Route
- Those factors still matter.
However, international shipping increasingly also requires attention to:
- Vessel sanctions
- Carrier background
- Insurance
- Transshipment locations
- Destination restrictions
- Cargo compliance
- Financial sanctions
The lowest freight price does not always represent the lowest overall shipping risk.
For high-value commercial cargo and complex international supply chains, transparent routing and compliant transportation are increasingly important.
Chinz Logistics International Freight Services
Chinz Logistics provides international sea freight, air freight and commercial logistics services, including:
- International sea freight
- International air freight
- LCL shipping
- FCL shipping
- Cross trade shipping
- Machinery transportation
- Commercial cargo shipping
- China warehousing
- Export customs support
- Destination customs and local delivery solutions
- Shipping options can be selected according to cargo type, origin, destination, sailing schedule and delivery requirements.
If you are preparing an international commercial shipment, provide:
Origin + destination + cargo description + quantity + weight + packed dimensions + Incoterm
to help determine a suitable international freight solution.
