High Court (Admiralty) — Judgment (summary)

Judge: Judge McDonald. Record summary prepared from the provided judgment text and fully anonymised.

Factual and Procedural Background

This action was brought by the Plaintiff (a UK‑domiciled telecommunications company within a larger corporate group) against the owners of an Irish-registered scallop trawler ("Vessel A") arising from damage to a subsea telecommunications cable (the "cable") laid in 1998 and running between a terminal in England and a terminal in Ireland. The cable contained multiple optical fibres and, together with its paired cable, carried substantial internet, television and telephone traffic between the United Kingdom and the island of Ireland at the relevant time.

On 26 January 2015 a network alarm indicated a communication break in the cable. The Plaintiff mobilised a repair vessel ("Repair Vessel B") to investigate; Repair Vessel B located physical damage and undertook repair works in early February 2015, recovering damaged cable and replacing a section of it. Repair Vessel B's contemporaneous log and report recorded several specific observations of damage and recovery operations. A second, separate area of damage to the same cable was identified later; that second area was the subject of separate proceedings which were settled before trial.

The Plaintiff sued the owners of Vessel A in the Irish High Court alleging that, while engaged in scallop trawling in the Sea Area on 26 January 2015, Vessel A's trawl gear snagged and damaged the cable. Proceedings were issued in November 2018; an appearance for the defendants was entered in January 2019. The defendants initially challenged ownership and other points; they also raised jurisdictional and technical defences which were not pursued to trial. The parties accepted Irish law as governing the dispute.

During trial the Court had to resolve multiple issues including ownership of the cable, whether the Plaintiff had suffered loss, whether Vessel A caused the damage, whether the defendants were negligent, whether the Plaintiff was contributorily negligent, and quantification of damages. There were contested factual and expert disputes (including shortcomings in some of the Plaintiff's evidence and later supplementation by an additional witness).

Legal Issues Presented

1. Is the Plaintiff the owner of the cable (i.e. has it established title) on the balance of probabilities?
2. Has the Plaintiff suffered loss such that it may recover damages, given that related group companies paid some costs?
3. Did Vessel A cause the damage to the cable (causation / factual responsibility)?
4. If Vessel A caused the damage, are the defendants legally liable in negligence for that damage (existence and scope of a duty of care in the context of fishing over known submarine cables)?
5. If liability is established, is the Plaintiff contributorily negligent for failing to monitor or maintain burial of the cable?
6. What is the appropriate quantum of damages (how to apportion and measure the repair costs)?

Arguments of the Parties

Plaintiff's Arguments

• The Plaintiff asserted ownership of the cable and relied on its internal fixed asset records, balance sheets and group accounting treatment to establish title on the balance of probabilities.
• The Plaintiff argued that it suffered loss when the cable was damaged and that the correct measure of loss is the reasonable cost of repair of a damaged chattel (relying on established authorities on chattel damage), regardless of which group company initially paid repair invoices.
• The Plaintiff contended that the cable was damaged by Vessel A's scallop trawling gear on 26 January 2015 and adduced expert and factual evidence (repair ship reports, AIS tracking, and expert analyses) to establish causation.
• On duty of care, the Plaintiff argued that established admiralty/common law authority recognises an obligation on mariners to take care to avoid damaging known submarine cables and that this duty should be held to apply to fishing vessels as well.
• In relation to quantification, the Plaintiff relied on the repair contractor's invoice (the consortium/repair agreement invoice) and related invoices and submitted an allocation method to reflect the two distinct repair events (one attributable to Vessel A and one to the other vessel). The Plaintiff sought judgment for the euro equivalent of the repair-related sums shown in the evidence.

Defendants' Arguments

• The Defendants challenged the Plaintiff's title to the cable and required formal proof of an unbroken chain of title from the commissioning party. They relied on contemporaneous letters, a cable crossing agreement and earlier English proceedings identifying the trading group company (not the Plaintiff) as owner, arguing that these documents supported the defence that the Plaintiff was not the owner.
• The Defendants argued there was no evidence the Plaintiff in fact suffered loss: a related trading company had paid repair invoices and the Plaintiff had not produced documentation showing any allocation/charge‑back to the Plaintiff.
• The Defendants denied causation: they accepted Vessel A was scallop trawling in the vicinity but disputed that, on the balance of probabilities, Vessel A's dredge caused the fibre break, highlighting gaps and errors in the Plaintiff's location/AIS evidence and expert opinions.
• On legal responsibility, the Defendants argued that (i) fishing over historical fishing grounds pre‑dated the cable and the Crown Estate licence contemplated continued public rights of fishing, and (ii) if the cable ought to have been continuously buried and monitored by the owner, that mitigation obligation lay on the Plaintiff rather than on the trawler. They submitted that, given lawful fishing activity, a duty of care in the manner contended for should not be imposed or, at least, that the Plaintiff was contributorily negligent.
• The Defendants also attacked the Plaintiff's quantum: they required detailed breakdowns and vouching for the large repair invoices, complained about the late and imprecise approach to apportionment between the two repair events and noted inconsistencies (including prior letters and proceedings that limited claims to 50% of costs in other fora).

Table of Precedents Cited

Precedent	Rule or Principle Cited For	Application by the Court
The Dictator [1892] P 304	Admiralty principle that an in rem action may give rise to personal liability against appearing owners; when owners appear they may be placed in same position as if personally summoned.	The Court noted the principle and recorded that the defendants no longer contested that the proceedings were properly in personam as well as in rem; thus this background authority supported the procedural posture of the case.
Sandy Lane Hotel Ltd v Times Newspapers Ltd [2011] 3 I.R. 334; [2014] 3 I.R. 369	Principles and difficulties associated with substitution of parties and potential consequences (statute of limitations and costs implications) when substituting a different group company as plaintiff.	The Court cited these decisions to underline that an application to substitute another group entity as plaintiff would be uncertain and potentially expose parties to costs and limitation objections; this influenced the Court's approach to assessing the Plaintiff's standing rather than permitting substitution.
Covidien Limited v The Revenue Commissioners [2025] IECA 75	Illustration (in a tax context) of corporate group structuring and how intra‑group arrangements can be respected for legal/financial purposes.	The Court referenced the decision by analogy when assessing the corporate group evidence and the normality of administrative arrangements where one group company provides services for others; it supported the view that group operational structures are commonplace and relevant to interpreting the MACSO arrangement.
Coles v Hetherton [2014] 2 All ER 223	The measure of damages for damage to a chattel that can be economically repaired is the reasonable cost of repair; the loss is suffered when the chattel is damaged and subsequent events are irrelevant to that direct loss.	The Court applied the principle to hold that the Plaintiff suffered loss upon the damage to the cable and was therefore entitled to damages measured by reasonable cost of repair, even though a related group company initially paid invoices; this defeated the Defendants' "no loss" knock‑out submission.
The London Corporation [1935] All ER Rep. 393	Authority for the proposition that, where a chattel is damaged and repaired, prima facie measure of damage is cost of repair.	The Court relied on this authority (and related admiralty authorities) to support the assessment of damages by reference to repair costs for the cable.
Dimond v Lovell [2002] 1 AC 384 (and earlier admiralty cases such as The Glenfinlas and The Kingsway)	Lord Hobhouse's exposition that damage to a chattel gives rise to a capital account loss measurable by cost to put chattel back in pre‑damage state; multiple admiralty authorities have long answered analogous questions.	The Court relied on this line of authority (as described in the opinion) to conclude that the reasonable cost of repair is the appropriate measure of loss for damaged cable and to reject the argument that the Plaintiff could not recover absent proof that it had itself paid repair costs.
Munnelly v Calcon [1978] I.R. 387	Irish authority on damages and restitutio in integrum; distinguishes irreparable damage cases (land/house) and illustrates reasonableness in awarding reinstatement costs.	The Court considered this Irish authority (concerned with real property) and held it not inconsistent with the English authorities relied on by the Plaintiff; Munnelly was used to show that the restitutio in integrum principle requires assessment of reasonableness and does not displace the approach taken in chattel cases.
Submarine Telegraph Co v Dickson (1864) 15 C.B. (N.S.) 760	Early admiralty/common law principle: mariners must exercise rights in navigation so as to avoid doing damage to property of others; duty applies at sea as on land.	The Court treated the case as foundational and persuasive authority supporting the imposition of a duty of care on mariners (including those engaged in fishing) to take reasonable steps to avoid damaging known submarine cables.
The Clara Killam (1870) L.R. 3 A & E 161	When a ship's anchor becomes entangled with a lawfully placed cable, the ship must take reasonable steps to disentangle without injuring the cable; severing is only justified if necessary for immediate safety.	The Court cited the principle to support the notion of concurrent rights and duties and the requirement that navigators act to avoid conflict with cable owners' rights; used to analogise the obligations of fishermen when cables are known to exist.
The Daphne (1934) 50 Ll. L. Rep. 51	Where a master anchors close to a known cable contrary to guidance and causes damage, the master may be negligent; the fact others sometimes do it is no defence.	The Court used it to illustrate the settled view that negligence can arise where a mariner takes avoidable risks around known cables and that customary practice does not excuse negligence.
Peracoma Inc v Société Telus Communications (2012) FCA 199	Canadian appellate recognition that ship operators/skippers owe duties to avoid damaging underwater cables shown on charts; application of neighbour/principle‑based negligence.	The Court cited the Canadian authority as supportive precedent showing comparable courts have applied the neighbour principle to cable damage by fishing vessels; it reinforced the conclusion that a duty of care extends to fishermen where cables are known and charted.
Donoghue v Stevenson [1932] AC 562	The neighbour principle: persons must take reasonable care to avoid acts or omissions likely to injure their "neighbour" — those closely and directly affected by their conduct.	The Court relied on Donoghue (conceptually) as the general foundation for imposing duty of care; it formed part of the analytical framework used to decide whether a duty should be recognised in this factual context.
The Tojo Maru [1972] AC 242	Historical discussion of negligence and the evolution of 'gross'/'culpable' negligence language.	The Court referred to the historical development of negligence concepts to reject an argument that older cases required a higher "culpable" standard to establish liability for cable damage.
Indermaur v Dames (1866) LR 1 CP 274; Grill v General Iron Screw Collier Co. (1866) LR 1 CP 600; Wilson v Brett (earlier)	19th century authorities illustrating the courts' language on negligence and that "gross negligence" is descriptive rather than a distinct legal standard.	The Court relied on these historical authorities when discussing the meaning of "culpable" or "gross" negligence in early submarine cable cases and to explain why ordinary negligence principles apply.
Grand Champion Tankers Ltd v Norpipe A/S [1984] AC 563; Carslogie SS Co v Royal Norwegian Government [1952] AC 292	Authorities addressing allocation of loss and the effect of multiple wrongdoers and the liability of the first wrongdoer for consequential delay/costs.	The Court cited these authorities when considering how repair and mobilisation costs should be apportioned between separate wrongdoers and in discussing legal principles relevant to quantum when there are sequential repairs.
Reaney v Interlink Ireland Ltd [2022] 1 I.R. 213	Principles governing awards of pre‑judgment interest under the relevant statute (s. 22 Courts Act 1981): interest is appropriate where the award is clear-cut and could/should have been paid earlier; otherwise discretion to refuse.	The Court relied on Reaney to exercise its discretion and refused an interest award, noting the complexity and delay in the proceedings and that the quantum and ownership issues were not "clear-cut".

Court's Reasoning and Analysis

Ownership of the cable

The defendants put the Plaintiff to proof of ownership. The Plaintiff's initial evidence on ownership (from Witness Hardman) was deficient in important respects: the witness relied heavily on second‑hand information, exhibited partial and redacted accounting screenshots (fixed asset register extracts) and failed to exhibit a complete chain of title tracing back to the party that commissioned the cable. The Defendants highlighted contemporaneous correspondence and contractual material (a cable crossing agreement and English proceedings) that suggested a different corporate trading entity (Company A) had identified itself publicly as the owner.

The Court examined the totality of the available evidence, including: the contemporaneous installation materials (including a marine survey evidencing the original contractor's role), the 2006 financial statements and directors' reports of the companies involved in the corporate transactions (which recorded a transfer of network assets and backbone network assets to the Plaintiff's predecessor), the Plaintiff's fixed asset register screenshots showing an asset entry for the cable (asset reference), and detailed evidence from Witness Egan (who had first‑hand knowledge of the Group's fixed asset registers from 2006 onward).

While there were gaps in formal documentary proof of an unbroken chain of title (and the Court noted the Plaintiff's failure to exhibit earlier agreements and to explain why certain enforcement steps were taken in the name of a related trading company in England), the Court applied the balance of probabilities standard. The Judge found that: (a) it was reasonable to infer the cable was originally commissioned by the historical commissioning party; (b) the 2006 asset transfer between Group companies was intended to transfer network/backbone assets to the Plaintiff's predecessor and that the cable has been recorded on the Plaintiff's asset register since circa 2006–2007; and (c) no other party had pressed a claim to ownership since then. The Court accepted that the Cable Crossing Agreement and the English proceedings naming Company A as claimant did not conclusively displace the Plaintiff's title because of the operation of the intra‑group management arrangement (the MACSO) that authorised Company A to act as agent in many respects and allowed Company A to contract in its own name for group activities. On balance the Court concluded that the Plaintiff had established ownership of the cable.

Has the Plaintiff suffered a loss?

The Defendants contended that the Plaintiff had not proved it suffered loss because a related group company (Company A) had paid repair invoices and no evidence of charge‑backs to the Plaintiff was produced. The Plaintiff relied on well‑established authorities that damage to a chattel gives rise to a direct loss at the moment of damage and that the reasonable cost of repair is the appropriate measure of that loss even if repairs are carried out or paid for by an insurer or another group company.

The Court accepted the legal authorities (in particular Coles v Hetherton and related admiralty/chattel authorities) and held that the Plaintiff suffered loss upon the damage to the cable and is entitled to damages measured by the reasonable cost of repair. The Court rejected the Defendants' "no loss" knock‑out, while noting the practical evidential difficulties produced by the Plaintiff's failure to show evidence of internal allocation of repair costs; but legal entitlement did not depend on the Plaintiff having personally paid the repair invoices.

Causation — did Vessel A cause the damage?

The causation enquiry was fact‑intensive and hinged on the correct plotting of the cable fault(s), the repair vessel's contemporaneous logs, the nature of the damage found on recovery, Automatic Identification System (AIS) data for Vessel A, and expert evidence.

The Court recorded that the Plaintiff's case initially relied on an OTDR‑derived "Fault Geo Position" which was not the same as the actual locations recorded by the repair ship when it physically inspected and recovered the cable. The Plaintiff's AIS expert had used limited AIS data (stored at two‑minute intervals and containing a critical four‑minute gap during the alarm period), producing misleading track plots. More comprehensive AIS data (30‑second interval data) was later obtained and plotted; this new data materially changed the position and timing analysis.

The Court carefully considered competing experts and factual witnesses. It found that (a) the physical condition of the recovered cable (armour deformation/mauling, severed core, local exposure) was consistent with trawl/dredge damage rather than an anchor; (b) Repair Vessel B's logs and photographs showed exposed cable over a small section with marine growth and discrete damaged points recovered during the lift; and (c) the more complete AIS data, when plotted, showed Vessel A's movements and two sharp starboard turns and contemporaneous speed reductions in the minutes surrounding the fault alarm. Fisheries evidence explained how dredges are towed and where dredges would lie relative to the trawler's stern (typically many tens of metres behind). The Court also accepted the expert evidence that snags from scallop dredges produce the observed damage patterns and can cause the cable to be pulled out of its trench before fibre breakage occurs.

The Court found that Vessel A was the only AIS/VMS‑transmitting vessel in the immediate area at the critical time and rejected the suggestion that an untracked smaller vessel was likely to have caused the damage given practical spacing of towed gear. Balancing all evidence (timings, AIS, repair ship log, physical appearance of cable, and expert explanation of fishing gear behaviour when snagging), the Court concluded on the balance of probabilities that Vessel A's dredge(s) snagged the cable and that this caused the fibre break.

Duty of care / Liability in negligence

The Court examined whether a duty of care in negligence existed between the defendants (operators/owners of Vessel A) and the Plaintiff (owner of the cable). Applying the approach cited from the Supreme Court guidance (Barlow), the Court first considered whether binding precedent mandated the duty; in the absence of binding Irish authority on precisely this factual nexus, the Court analyzed analogous historical admiralty authorities.

The Court relied on the Submarine Telegraph Co. v Dickson line of authorities and subsequent cases (including The Clara Killam, The Daphne and Canadian authorities) to conclude there is a well‑established principle that mariners must exercise rights of navigation so as to avoid damage to other parties' property (including submarine cables). That principle, the Court held, is apt to be applied to fishing vessels: concurrent rights to use the seabed (cable owners and fishers) must be exercised so as to avoid foreseeable harm. The Court rejected the defendants' contention that the Crown Estate licence, pre‑existing fishing activity, or the possibility that the cable might have been exposed in places, meant fishermen had a free licence to fish indifferent of risk. The Court found that practical steps are available to fishermen (for example, hauling gear before crossing a cable route) and that, given warnings on charts and industry awareness programmes, trawlers owed a duty to take reasonable steps to avoid snagging known and charted cables.

The Court therefore held that the defendants owed a duty of care to the Plaintiff and that, on the facts found (Vessel A snagging the cable and reasonable precautions available), the defendants were negligent and liable for the damage.

Contributory negligence

The Defendants bore the burden of proving contributory negligence by the Plaintiff (e.g., failure to monitor or rebury the cable). The Court reviewed industry evidence on burial depths, installation practice, the practical limits of monitoring (surveys provide only a "snapshot" and exposed areas may become reburied) and the Plaintiff's practices. The Court found no persuasive evidence that the Plaintiff had been contributorily negligent in a way that should reduce recovery: the absence of periodic surveys did not make the Plaintiff culpable in circumstances where surveys would be of limited utility and may be counter‑productive if their results were relied upon as static.

Quantum

The Court scrutinised the repair contractor's invoice (the consortium daily rate and variable charges) and supporting logs. The Plaintiff's approach to quantum and to apportionment between the two separate repair events was criticised by the Court for lack of advance pleading and a failure to call witnesses able to explain and vouch the detailed repair cost breakdowns. The Court nonetheless analysed the repair operator's own report and daily log, adjusted apparent over‑claimed mobilisation/demobilisation hours where unsupported, apportioned certain variable costs pro rata to the time reasonably attributable to the repair of the first (relevant) fault, excluded an unexplained port charge, and accepted the reasonable daily rate and a reasonable fee for the Plaintiff's on‑site advisor.

Summarising the Court's factual accounting adjustments (as set out in the judgment), the Court concluded that the Plaintiff could recover the United States dollar aggregate of the fixed day charges and allowable variable charges shown in the evidence (US$397,514.02) and an additional fee for the Plaintiff's representative (GBP £9,000). The Court directed that judgment be entered for the Plaintiff for the euro equivalent of those sums (the exact euro conversion to be agreed because the judgment was expressed as euros equivalent of the USD/GBP totals).

Interest

The Plaintiff sought statutory pre‑judgment interest under the relevant statute. The Court applied Reaney and relevant discretion criteria and refused interest, observing that ownership, liability and quantum were not clear‑cut in the circumstances, that there had been significant delay in prosecution and that complexities and conduct issues made an interest award inappropriate.

Holding and Implications

Core Rulings:

• Ownership: On the balance of probabilities the Court found that the Plaintiff is the owner of the cable.
• Causation and Liability: The Court found, on the balance of probabilities, that Vessel A's dredge(s) caused the break in the fibre; the Defendants were negligent in failing to take reasonable steps to avoid damaging the cable and are liable to the Plaintiff in negligence.
• Damages: The Court assessed recoverable repair‑related sums as the USD and GBP amounts recorded in the judgment (aggregate US$397,514.02 and GBP £9,000) and directed judgment for the euro equivalent of those sums; a specific euro figure was to be agreed/converted between the parties.
• Interest: The Court refused an award of statutory pre‑judgment interest under the relevant statute.

Implications:

• The judgment recognises and applies long‑standing admiralty/common law principles that operators of vessels owe a duty to avoid damage to known submarine cables; that duty was held to extend to fishing vessels engaged in lawful trawling where reasonable steps were available to avoid harm.
• The decision emphasises evidential standards in ownership and quantum: group accounting records and financial statements can be decisive in establishing ownership on a balance of probabilities where formal documentary transfer instruments are incomplete, but gaps and late documentary disclosure attract cost consequences and judicial comment.
• On damages, the Court applied the established measure for chattel damage — the reasonable cost of repair — and confirmed that a claimant need not have itself incurred payment of invoices to recover that loss; events after the damage (including who actually paid for repairs) do not negate the direct loss suffered on damage.
• The Court declined to set aside the established principles underpinning admiralty protection of submarine cables, but the judgment also recognises practical industry considerations (plough limits, single/double armour decisions, and limited utility of periodic surveys) when assessing responsibilities of cable owners and mariners.

Note: This summary is confined to the matters and findings described in the judgment text provided. It omits identifying particulars and replaces all personal and corporate names and place names with consistent anonymised placeholders. Where the judgment left any conversion to be agreed (for example the euro equivalent of USD/GBP awards), the summary records the position used by the Court (i.e. judgment for the euro equivalent as directed by the Court).