Legal Issues Arising from Damage to Submarine Cables Caused by Ships under Korean Law

This blog post reproduces an article the author contributed in 2026 to The Legal 500 Country Comparative Guides, Hot Topic | Shipping.

I. Submarine cables: critical infrastructure of the digital age

In modern society, submarine cables have established themselves as core national infrastructure beyond mere communication connection means. Since the first submarine telegraph cable was experimentally installed in the Dover Strait in 1850, as of 2025 there are 597 submarine cables in operation or under construction worldwide, with a total length of approximately 1,480,000 km. Considering that satellite communications handle only 0.37% of total data transmission, it can be said that more than 99% of global international data traffic is transmitted through submarine cables. Therefore, submarine cables are irreplaceable core infrastructure in modern society.

Particularly after the COVID-19 pandemic, as non-contact activities such as remote work, online education, and digital healthcare became widespread and commonplace, dependence on submarine cables has deepened further. Recently, global big tech companies such as Google, Meta and Microsoft have also begun to directly own submarine cables, and the number of big tech company-owned submarine cables, which was only 20 in 2017, has increased to 69 as of February 2024. This can be considered an indicator showing how important submarine cables are in the modern digital age.

Submarine cables were previously considered safe due to their “triple invincibility,” namely being located in deep seabeds, far from land, and technically robustly constructed. However, as dependence on submarine cables has recently increased, there also has been an increased awareness that the scale of damage can be astronomical when submarine cables are damaged. In particular, submarine cable damage by vessels can emerge as a new risk for shipowners.

1. Increasing submarine cable damage accidents and various causes, emergence of new threats

Submarine cable damage occurs approximately 150-200 times annually, showing a gradually increasing trend with 201 cases in 2023 and 204 cases in 2024. By region, the South China Sea is the most dangerous area where submarine cable failures occur every few weeks, and more than 50 repairs are performed annually in the Atlantic as well.

According to analysis from 2010-2023, approximately 65% of annual submarine cable accidents are confirmed to be due to fishing and vessel activities. Cases of trawl fishing gear or dredgers getting caught on submarine cables and pulling or cutting them continue to occur, and damage from vessel anchor dragging also accounts for about 30%, making it a major cause.

Meanwhile, submarine cable cutting incidents have occurred consecutively recently. In November 2024, two submarine communication cables were cut in Swedish territorial waters, with a Chinese cargo ship suspected of involvement. In December 2024, a submarine power cable between Finland and Estonia was damaged in the Baltic Sea, and a Russian tanker, the suspected vessel, was seized and investigated in Finland. In January 2025, a submarine communication cable installed off the northern coast of Taiwan was cut, with a Cameroon-flagged Chinese cargo ship suspected of deliberately cutting it. In February 2024, submarine cable damage in the Red Sea affected 25% of Asia-Europe-Middle East traffic, causing economic damage of approximately USD 3.5 billion. Three submarine cables were damaged, with the anchor of a ship that sank after being attacked by Houthi rebels identified as the cause. In the 2024 West African submarine cable cutting accident, four submarine cables were simultaneously damaged, causing Nigeria to suffer economic losses of approximately USD 593.6 million over four days, and West Africa as a whole suffered loss of approximately USD 6.66 billion over three days.

Recent submarine cable cutting incidents are evaluated as sabotage, which is a “gray zone” offensive between military attacks and accidental incidents where accurate cause identification is often difficult.

2. Additional risks increased by the expansion of the offshore wind power industry

Additionally, the rapid growth of the offshore wind power industry is also expected to cause new problems related to submarine cables. Europe targets offshore wind power generation capacity of 60GW by 2030 and 300GW by 2050, while Korea presented a target of 12GW offshore wind power generation capacity by 2030 in the Renewable Energy 3020 Implementation Plan announced in 2018. According to recent market analysis, the target may be upwardly adjusted to 18-20GW. In the offshore wind power industry, transmission and distribution account for 32% of wind farm construction costs, showing a high proportion of submarine cables, and complex submarine cable networks are needed to connect offshore wind turbines to offshore substations and onshore substations. Therefore, large quantities of submarine cables will be concentrated around offshore wind farms, and vessels operating in nearby waters may be judged as having known or being able to know the possibility of multiple submarine cables existing on the seabed even if their locations are not marked on nautical charts.

II. Submarine cable protection

1. International conventions and their limitations

International conventions for submarine cable protection include the 1884 Paris Convention (Convention for the Protection of Submarine Telegraph Cables) and the 1982 United Nations Convention on the Law of the Sea (UNCLOS). The 1884 Paris Convention requires each country to stipulate submarine cable damage due to intent or gross negligence as a punishable crime. Article 113 of the 1982 United Nations Convention on the Law of the Sea stipulates that, “Every State shall adopt the laws and regulations necessary to provide that the breaking or injury by a ship flying its flag or by a person subject to its jurisdiction of a submarine cable beneath the high seas done willfully or through culpable negligence, in such a manner as to be liable to interrupt or obstruct telegraphic or telephonic communications, and similarly the breaking or injury of a submarine cable pipeline or high voltage power cable, shall be a punishable offence.” However, the current international legal system has limitations in responding to modern threats to submarine cables and is particularly insufficient as an effective deterrent against gray zone attacks or sabotage covertly supported by some countries.

2. Korea’s submarine cable protection regulations

There are not yet many special regulations regarding submarine cable protection in Korea. The Electric Utility Act allows the Minister of Trade, Industry and Energy to designate underwater line protection zones upon application by electric utility operators to protect underwater lines such as electric lines installed underwater (Article 69), prohibits acts that may damage underwater lines such as dropping ship anchors within protection zones (Article 70), and stipulates that violators shall be punished by imprisonment for not more than 3 years or a fine not exceeding 30 million Korean won (Article 101).

The Telecommunications Business Act prohibits anyone from damaging telecommunications facilities or interfering with their functions to obstruct telecommunications and stipulates that the Minister of Science and ICT may designate submarine cable boundary zones upon application by common carriers (Article 79). Anyone who damages or interferes with telecommunications facilities may face imprisonment for not more than 5 years or a fine not exceeding 200 million won (Article 94).

As general provisions, the crime of property damage under the Criminal Act (Article 366) and tort-based liability for damages under the Civil Act (Article 750) may apply.

A. Analysis of Korean precedents related to submarine cable damage accidents by vessels

Under Korean law, when submarine cable damage accidents by vessels occur, (1) criminal liability can be imposed on captains based on the Electric Utility Act, the Telecommunications Business Act, or property damage under the Criminal Act, (2) liability for damages based on tort can be imposed on shipowners, and (3) the Korea Maritime Safety Tribunal can issue disciplinary decisions such as business suspension to maritime accident-related persons.

However, the core issue in the above legal procedures is whether the vessel (mainly the captain) breached the duty of care. In the past, identifying the vessel that damaged submarine cables was important, but with technological advancement, the time of the incident can be confirmed through monitoring data on when communication or power signals were disconnected, and suspected vessels can be identified through information from Vessel Traffic Service Centres, AIS data, etc. Specific evidence can also be secured through underwater filming footage and investigation of anchors and fishing gear, so vessel identification is no longer a main issue. Therefore, the core issue has become whether the vessel violated the duty of care, particularly whether the vessel knew or could have known of the submarine cable’s existence is most important. In this regard, it is necessary to understand the duty of care expected of vessels and submarine cable installers by Korean courts through precedents related to submarine cable damage accidents.

• Supreme Court Judgment rendered in 2011

The Supreme Court recognised the vessel’s negligence in a case where a tugboat captain anchored too close to a submarine communication cable while seeking shelter from bad weather and was negligent in monitoring anchor dragging: ① failing to understand the meaning of submarine communication cable symbols displayed on nautical charts and GPS plotters to anchor in a safe location, but instead anchoring only 200m away from the submarine communication cable installation site without recognizing the meaning of the symbols; ② overlooking the need to ensure that the anchor could secure sufficient holding power; and ③ being negligent in monitoring anchor dragging through radar and GPS plotter surveillance after anchoring, thus completely failing to notice anchor dragging.

• Busan District Court Judgment rendered in 2020

The Busan District Court recognised professional negligence in a case where a tugboat captain anchored without checking the area where submarine cables were laid and damaged submarine cables: ① the captain had obligations under the Seafarer Act to maintain the latest nautical charts and to request the shipowners to provide the latest nautical charts, but ② failed to check nautical charts or GPS plotters that could confirm the submarine geological and topographical conditions of the waters and did not request the shipowners to provide the latest nautical charts or GPS plotters, and ③ ordered anchoring without checking areas where submarine cables were laid.

• Busan District Court Judgment rendered in 2023

In a case where a tugboat fleet conducted emergency anchoring to avoid strong winds near Busan Port waterway, which was an area where submarine cables were laid but their location was not marked on nautical charts and was only marked as an anchoring restriction zone, the Busan District Court determined that the vessel did not breach the duty of care because the vessel recognised the existence of submarine cables, despite the submarine cables having been damaged due to anchoring.

This can be summarised as follows:

(1) Master’s duty of care

a. Obligation to maintain and check latest nautical charts: Master should obtain the latest nautical charts before departure and accurately identify the locations of obstacles such as submarine cables marked on charts.

b. Duty of care in selecting anchorage: Master should check locations where submarine cables are laid and select anchorage at a safe distance.

c. Obligation to monitor anchor dragging: Master should continuously monitor whether anchors are dragging through radar and GPS plotters after anchoring.

d. Obligation to request from shipowners: Master should request appropriate measures such as obtaining the latest nautical charts from shipowners when there are problems with nautical charts or navigation equipment.

(2) Shipowners’ duty of care

a. Obligation to maintain latest nautical charts: Shipowners must maintain the latest nautical charts and navigation publications on vessels in accordance with the Ship Safety Act.

b. Obligation to manage and supervise seafarers: Shipowners must exercise considerable care in the selection and supervision of captains and seafarers who are employees in accordance with Article 756 of the Civil Act.

It was further held that submarine-cable installers are under an obligation to provide accurate cable-location information to the relevant authorities and to ensure that such locations are correctly reflected on nautical charts. Accordingly, where submarine-cable locations are not shown on the nautical charts, a vessel may not be found to have breached its duty of care when anchoring in the vicinity, as it could not reasonably have known of the cable’s existence. Moreover, even where a vessel is deemed to have been capable of knowing the cable’s existence, a failure by the cable installers to ensure accurate charting of the cable route may constitute contributory negligence.

• Special legal issues related to offshore wind power

Offshore wind farms require various types of submarine cables including power cables, communication cables, and control cables, each of which may have different owners and operators. Since offshore wind power projects are mostly conducted by consortium-based operators, the liability structure can become complex in case of submarine cable damage. For example, when multiple cables are simultaneously damaged within an offshore wind farm, the number of accidents may become an issue in insurance or limitation of liability proceedings, and there is also a possibility of receiving damage compensation claims from multiple parties, where proving the causal relationship of each damage can also become an issue. Additionally, power cable repair costs are much higher than communication cables, so the compensation burden is expected to be further increased.

Meanwhile, waters near offshore wind farms may be designated as navigation restricted or navigation-prohibited zones in the future. In the event of accidents occurring within such zones or near their boundaries, vessels may be held to a higher duty of care than in general navigable waters. In fact, due to the presence of wind turbines, current and wind patterns in the vicinity of offshore wind farms may differ from those in ordinary waters, and heighted caution is expected to be required when operating vessels in such areas. This distinctiveness may influence the assessment of negligence.

B. Scope of damage compensation for submarine cable damage

Damage compensation for submarine cable damage should be thoroughly reviewed as the amount can be very large.

• Cable repair costs

Generally, communication cable repair costs are reported to average USD500,000~1,000,000 per case, while power cables can reach USD10,000,000~100,000,000. These costs vary depending on the damage extent, underwater depth, weather conditions, repair vessel mobilisation costs, etc. and generally constitute ordinary damages that can be easily proven.

• Loss of earning

Business losses may arise from interruptions to communications or power supply interruption caused by submarine cable damage, and such losses can be astronomical in scale. A substantial causal link between submarine cable damage and the specific business losses must be established, and an important criterion is whether the shipowners and crewmembers could have foreseen such losses at the time the damage occurred.

III. Practical response measures

• Initial response system for accidents

Establishing a systematic initial response protocol is importance because it is often difficult for vessels to immediately recognise the occurrence of submarine cable damage accidents. Generally, after submarine cable owners or operators recognise damage accidents and request investigation from the maritime police, the maritime police find suspected vessels and notify shipowners, allowing shipowners to recognize accidents after the fact. At this time, shipowners should instruct captains to thoroughly preserve evidence such as navigation logs, VDR records, AIS data, electronic chart records, anchoring and weighing positions, number of shackles used during anchoring, weather conditions at the time, seafarer statements, and anchor and gear conditions. Particularly, AIS data and electronic chart records are very important evidence in disputing vessel negligence. Cases have been confirmed where AIS was turned off immediately after recognising submarine cable damage, which is an absolutely unacceptable response.

• Ship arrest

Submarine cable owners can provisionally seize vessels to preserve damage compensation claims. Korean courts tend to accept only cash deposits for releasing vessel provisional seizures, and therefore shipowners would need to negotiate with the submarine cable owners to seek release the vessel from the arrest with P&I guarantee letters.

• Precautions during damage assessment

It would be important to accurately identify the scope of damage compensation during damage assessment and actively dispute excessive claims. Particularly for business losses, causal relationship and foreseeability must be strictly reviewed, and careful examination is needed to determine whether the damage claim presented by submarine cable owners or operators matches the actual damages. Additionally, when there is negligence by submarine cable owners or operators (e.g., failure to mark on charts, provision of inaccurate location information, etc.), contributory negligence should be actively argued to reduce the compensation level.

• Necessity of initiating limitation of liability proceedings

Liability for damages due to submarine cable damage may include not only repair costs, but also business losses due to cable damage. Therefore, shipowners who receive claims for submarine cable damage need to immediately consider initiating limitation proceedings. Since liability limits under limitation proceedings are calculated based on vessel tonnage, damage compensation liability can be significantly limited.

However, acts of deliberately damaging submarine cables such as sabotage may prevent the shipowners from initiating the limitation proceedings.

For reference, Korea has only incorporated the contents of the 1976 LLMC into domestic law but has not officially joined the LLMC. Therefore, the possibility of duplicate limitation fund issues should also be kept in mind.

IV. Conclusion

Submarine cable damage accidents are emerging as new risk factors in the digital age and can impose high damage compensation risks on shipowners. Therefore, shipowners should strengthen seafarer education and secure the latest nautical charts and navigation equipment from a preventive perspective, while establishing strategies to minimize damage through rapid initial response and expert appointment when accidents occur. Particularly, effective management of damage compensation amounts through active utilisation of limitation proceedings and systematic negotiations is expected to be important. As submarine cable damage accidents are now establishing themselves as core risks that the shipping industry must prepare for, comprehensive response measures at the shipping industry level are urgently needed.

K. M. Choi is a partner at Law Offices Choi & Kim, qualified in the Republic of Korea, with over ten years in shipping disputes, marine insurance and major casualties in Korean waters. He can be reached at kmchoi@choikim.com or on LinkedIn.

This article describes Korean law and practice in general terms and is not advice on the law of any other jurisdiction. The law is stated as at the date of the original Korean publication and may since have changed, and nothing here creates a lawyer–client relationship.