Under the Jones Act, a vessel is any watercraft or structure that is practically capable of being used for transportation on water — this includes ships, barges, drilling rigs, dredges, and crew boats, not just traditional seafaring vessels. The U.S. Supreme Court established this definition in Stewart v. Dutra Construction Co., 543 U.S. 481 (2005).
Whether the structure you worked on qualifies as a vessel determines which federal law governs your injury claim — and what compensation you can recover. Jones Act seamen on qualifying vessels can sue their employers for negligence and recover full damages including pain and suffering. Workers on fixed structures that don’t qualify as vessels are covered instead by OCSLA or the LHWCA, which provide different remedies. This post explains the legal test courts use to make that determination.
Why Vessel Classification Determines Your Jones Act Rights
The Jones Act gives qualifying maritime workers the right to sue their employer for negligence after a work-related injury — a protection that doesn’t exist under standard workers’ compensation. To qualify, you must be a seaman working on a vessel in navigation. Whether the structure you were injured on qualifies as a vessel is often the first — and most critical — question in a Jones Act case.
Not sure whether you qualify as a seaman? Read our full guide to Jones Act seaman status and the 30% rule.
Why Does a Vessel’s Definition Matter for a Jones Act Claim?
However, to prevail in a Jones Act lawsuit, you must first be able to prove that you meet the qualifications for being a “seaman” as defined under the law. Two key qualifications used to determine seaman status are:
- The worker had an employment-related connection to a vessel or group of vessels that was substantial in terms of both duration and nature.
- The worker contributed to the mission or operation of a vessel or group of vessels in navigation.
Because of this, the definition of a vessel under the Jones Act can hold serious legal significance for maritime workers. If a worker is classified as a seaman, they are granted the right to seek compensation for injuries caused by employer or crew member negligence. They are also are entitled to maintenance and cure, covering living expenses and medical treatment during recovery.
The Legal Definition of a Vessel Under the Jones Act
A vessel is any watercraft or structure practically capable of transportation on water — including ships, barges, tugboats, semi-submersibles, drilling rigs, and floating work platforms. A vessel does not need to be self-propelled or even moving at the time of an injury to qualify. A structure is considered “in navigation” if it is floating, operational, and capable of movement on navigable waters. This means an injured worker on a stationary jack-up rig or anchored barge may still have a Jones Act claim — a vessel remains in navigation even when sitting still in the water. A structure only loses its vessel character if removed from the water for an extended period.
Mobility and Navigation: What Makes Something a Vessel
A key distinguishing feature of a vessel under the Jones Act is its mobility and ability to navigate on water. In order to be considered a vessel, it should have the capability to move independently, either by its own power or by being towed.
Additionally, a vessel must possess the necessary equipment and mechanisms to navigate through water, such as propulsion systems and steering controls. Furthermore, the vessel’s ability to transport cargo, passengers, or equipment is also an important aspect of its definition. These features set vessels apart from other watercraft that may not meet the criteria of mobility and navigation.
Do Special-Purpose Craft Count? Dredges, Barges, and Jack-Up Rigs
Special purpose watercrafts, like dredges or construction barges, may be considered vessels depending on their characteristics and intended use. Their ability to navigate and transport personnel or equipment is crucial in determining their vessel status. Legal interpretations and specific requirements also come into play. Consulting a maritime lawyer can provide clarity on the vessel classification under the Jones Act.
Vessel types that typically qualify under the Jones Act:
- Supply boats and crew boats
- Tugboats and towboats
- Barges (including construction and crane barges)
- Jack-up drilling rigs and semi-submersible rigs
- Mobile offshore drilling units (MODUs)
- Dredges
- Drillships
- Floating dormitories and liftboats
- Pontoon rafts
Structures that generally do NOT qualify:
- Fixed offshore platforms permanently attached to the seabed
- Tension leg platforms (TLPs), SPARs, and FPSOs permanently moored in one location
- Permanently moored floating structures with no meaningful navigational function
Note: Vessel status for jack-up rigs and MODUs can depend on whether the structure was in transit or drilling at the time of injury — this is a fact-specific determination courts make case by case.
Does Vessel Ownership or Flag Affect Your Jones Act Rights?
Vessel ownership and flag are not the determining factors in whether a watercraft qualifies as a “vessel” for seaman status purposes. An injured worker on a foreign-flagged vessel may still qualify as a Jones Act seaman if the other requirements are met. However, ownership and flag registration do affect other aspects of maritime law — particularly the Jones Act’s cabotage provisions governing domestic trade routes. An LKSA attorney can clarify how vessel ownership affects your specific claim.
Supreme Court Cases That Define What Counts as a Vessel
Stewart v. Dutra Construction Co. (2005) — Dredges Can Be Vessels
In Stewart v. Dutra Construction Co., 543 U.S. 481 (2005), the U.S. Supreme Court held unanimously that a dredge — a specialized watercraft designed to excavate underwater sediment — qualified as a vessel under the Jones Act. The court established that the federal definition of vessel applies to the Jones Act: any watercraft or artificial contrivance used or capable of being used as a means of transportation on water. The dredge in Stewart was capable of transportation on navigable waters, regardless of its specialized purpose, and therefore qualified. This decision opened Jones Act protections to workers on a wide range of specialized craft beyond traditional ships.
Lozman v. City of Riviera Beach (2013) — The Practical Observer Test
In Lozman v. City of Riviera Beach, 568 U.S. 115 (2013), the Supreme Court addressed a floating home that was towed from location to location on navigable waters. The court held the floating home was not a vessel, establishing the “reasonable observer” test: would a reasonable observer consider the structure designed to a practical degree for transportation on water? The floating home in Lozman was used exclusively as a residence with no meaningful navigational function — it failed this test. The practical observer test focuses on the structure’s design and purpose, not merely its ability to float.
2025 Update — Offshore Wind and OCS Vessel Questions:
The Fifth Circuit in 2025 addressed Jones Act vessel compliance in the emerging offshore wind sector, affirming the dismissal of a challenge to a CBP ruling over whether foreign vessels could perform scour protection installation on OCS wind farm sites. While this case (Great Lakes Dredge & Dock v. CBP) was not a seaman injury case, it confirms that the Jones Act’s reach to OCS structures and the question of what qualifies as a vessel remain actively litigated as new vessel types enter offshore markets. Workers on offshore wind installation vessels, crew transfer vessels, and cable-laying ships in the Gulf of Mexico and Atlantic face similar vessel status questions to those on traditional oil and gas structures.
What Does NOT Qualify as a Vessel Under the Jones Act?
Understanding what does not qualify is as important as understanding what does. Certain offshore structures are specifically excluded from vessel status, which means workers on these structures typically cannot bring Jones Act claims:
- Fixed offshore platforms permanently attached to the seabed do not qualify as vessels. Workers on these structures are generally covered by the Outer Continental Shelf Lands Act (OCSLA) instead, which extends LHWCA workers’ compensation benefits to OCS workers who do not qualify as seamen.
- Permanently moored structures that have lost their navigational function — such as a floating casino or floating restaurant anchored indefinitely in one location — are generally not vessels under the Lozman practical observer test.
- Dry docks in certain configurations may not qualify as vessels depending on their design and use.
Important clarification: Jack-up rigs and semi-submersible rigs generally DO qualify as vessels under the Jones Act because they are designed to move between locations and are capable of flotation — even when stationary over a drill site. The structures that do not qualify are truly fixed platforms permanently attached to the seabed, and permanently moored structures that have lost navigational capability. If you worked on a jack-up rig, semi-submersible, drillship, or mobile offshore drilling unit (MODU), you likely have a Jones Act claim worth evaluating.
If you worked on a structure and are unsure whether it qualifies as a vessel, the distinction is critical — it determines whether you have Jones Act rights or LHWCA/OCSLA rights, which provide different remedies and different compensation structures.
Unsure whether the structure you worked on qualifies as a vessel? Talk to an LKSA Jones Act attorney — free, confidential case review.
What Vessel Classification Means for Your Injury Claim
The classification of the structure you worked on at the time of your injury directly determines what you can recover:
• If the structure qualifies as a vessel and you qualify as a seaman, the Jones Act allows you to sue your employer for negligence and recover full damages — including medical expenses, lost wages, diminished earning capacity, pain and suffering, and emotional distress. You are also entitled to maintenance and cure benefits from the date of injury regardless of fault.
• If the structure does not qualify as a vessel, you are likely covered by OCSLA or the LHWCA, which provide a federal workers’ compensation system. These laws offer different benefits, do not include a right to sue for negligence, and generally provide lower maximum recoveries than a successful Jones Act claim.
The difference in potential compensation between a Jones Act claim and an LHWCA/OCSLA claim can be substantial. Vessel classification is one of the first things an LKSA attorney will analyze in evaluating your case.
Unsure Whether Your Worksite Qualifies? Talk to an LKSA Attorney
Knowing if your maritime injury is covered by the Jones Act can make a significant difference in obtaining compensation and support. If you have been injured while working on a vessel or in a maritime capacity, it is important to consult with an experienced maritime attorney to understand your rights and options.
LKSA has litigated vessel classification and seaman status questions in the Eastern District of Louisiana for over 35 years. Our attorneys have argued cases that shaped the legal requirements for a person and a vessel to be governed by the Jones Act — including work in the Deepwater Horizon and SEACOR Power litigations. Paul Sterbcow served as Co-Lead Trial Counsel in the Deepwater Horizon liability trial, which resulted in a settlement of $14,421,477 for four injured rig workers in the Eastern District of Louisiana. Ian Taylor was appointed to the Executive Committee in the SEACOR Power litigation.
LKSA’s attorneys have argued vessel status and seaman classification questions before the Eastern District of Louisiana — the federal court that handles more Jones Act cases than any other district in the United States.
Call 504-588-1500 to schedule a consultation with one of our experienced Jones Act lawyers in Louisiana.
