Maritime Autonomous Surface Ships: A critical 'MASS' for legislative review

13 December 2022

Written by Argyro Kepesedi, Article No. 97 [UNCTAD Transport and Trade Facilitation Newsletter N°96 - Fourth Quarter 2022]

Maritime Autonomous Surface Ships
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To keep pace with varying degrees of ship automation the legal framework for shipping may need to be adapted. Following a regulatory scoping exercise, relevant work progressing at the IMO is of considerable interest.

Automation in the maritime sector

The maritime industry has always been a sector where innovation and cutting-edge technology find application, and the need for increased efficiency and operational safety has led to the development of various levels of automation both on board vessels and ashore. Examples include, among others, situational awareness sensors, autonomous navigation systems, off-ship communication technologies, and robotics.[1]

The elimination of the human element might significantly reduce the possibility of human error,[2] but it also opens a pandora’s box of other risks. From the simplest malfunction, such as power failures, to more menacing ones, such as cyber/radio frequency/satellite attacks, automated systems have their own weak spots.[3] Risks vary depending on levels of automation and degrees of autonomy, with fully autonomous vessels posing a range of particular and entirely new challenges.

Maritime Autonomous Surface Ship (MASS)

According to the IMO, "Maritime Autonomous Surface Ship (MASS)" refers to a ship which, to a varying degree, can operate independent of human interaction. Degrees of automation have been distinguished as follows:

  • Degree 1: Ship with automated processes and decision support: Seafarers are on board to operate and control shipboard systems and functions. Some operations may be automated and at times be unsupervised but with seafarers on board ready to take control.
  • Degree 2: Remotely controlled ship with seafarers on board: The ship is controlled and operated from another location. Seafarers are available on board to take control and to operate the shipboard systems and functions.
  • Degree 3: Remotely controlled ship without seafarers on board: The ship is controlled and operated from another location. There are no seafarers on board.
  • Degree 4: Fully autonomous ship: The operating system of the ship is able to make decisions and determine actions by itself.

Legal implication of MASS

While technology and automation both on board and on shore have evolved over the past decades, the same cannot be said for the legal framework governing maritime transport. Since the advent of shipping, seafarers have been integrally involved in ship operations, appropriate manning is considered an essential element of the seaworthiness of a ship and a prerequisite to ensure authorization to operate in national and international waters.  

The outsourcing of some activities to mechanical counterparts and the lack of crew requires the re-thinking of several legal obligations undertaken by the flag states to certify the function of a vessel and could alter the liability regimes in which commercial ships operate. For example:

  • Would automated ships with no crew on board be considered as seagoing vessels under UNCLOS, international and national law?
  • How would minimum manning requirements for various tasks onboard the ship (such as watchkeeping, anchoring, loading and discharge) have to evolve to consider extensive automation?
  • How would training of the existing crew develop to familiarize the crew with new digital tools?
  • Could automated systems react in exceptional situations requiring situational judgement such as decision-making to avoid collisions /respond to pollution incidents and deviations to save human life at sea?
  • Would remote operators based at the shore be considered seafarers?
  • Could manufacturers of a devise/faulty component of an automation system be liable for the damages caused due to a malfunction? Would they be covered by a limitation of liability regime?

Other questions arising are whether all national jurisdictions would allow the operation of MASS in their waters[4] and, importantly, how saving life and property at sea can be ensured in practice, in the absence of any crew on board.

Those questions are of significant importance, including for developing States, which account for over 80% of flag states[5] and are among the major seafarer- supplying jurisdictions[6].  A harmonization of the legal framework surrounding the subject (through either soft law or binding legal instruments) would both increase the safety of navigation and facilitate trade.

As highlighted in UNCTAD’s Review of Maritime Transport 2019, it would also ensure that seafarers originating from developing states are re-skilled in accordance with the more recent needs and requirements of an automated reality on board of MASS, as automation could render some tasks onboard obsolete.

IMO scoping exercise for the use of MASS

In response to the numerous questions arising on the subject and to ensure that regulation remains pertinent in the light of technological developments, the IMO initiated in 2017 a regulatory scoping exercise for the use of maritime autonomous surface ships (MASS) by the Maritime Safety Committee (MSC), as well as the Legal (LEG) and Facilitation (FAL) Committees, which was concluded in 2021. The goal of the scoping exercise was to assess existing IMO instruments to see how they would apply to ships with varying degrees of automation.

The MSC, in June 2021 in the outcomes of the regulatory exercise concluded that some high priority issues would need to be addresses in respect of several maritime conventions focusing on the safety of navigation, such as the International Convention for the Safety of Life at Sea 1974 (SOLAS) as amended; the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers, 1978 (STWC) as amended; the International Convention for the Prevention of Pollution from Ships, 1973-1978 (MARPOL) as amended; and the  Convention on the International Regulations for Preventing Collisions at Sea 1972 (COLREGs).

Those included:

  • The development of MASS terminology and definitions for the meaning of the terms ‘‘MASS’’, “master”, “crew” or “responsible person”, particularly in Degrees Three (remotely controlled ship) and Four (fully autonomous ship).
  • The functional and operational requirements of the remote-control station/center and the possible designation of a remote operator as seafarer.
  • The revision of provisions relating to manual operations and alarms on the bridge and other actions by the personnel (such as firefighting, cargoes stowage and securing and maintenance); watchkeeping; implications for search and rescue; and information required to be on board for safe operation.

The LEG, in December 2021, on the other hand arrived at the conclusion  that the existing provisions of the international conventions under its purview (such as for example the  International Convention on Civil Liability for Oil Pollution Damage 1969 and its 1992 Protocol, the International Convention on the Establishment of an International Fund for Compensation for Oil Pollution Damage 1971 and its 1992 Protocol (FUND), the International Convention on Civil Liability for Bunker Oil Pollution Damage 2001 (BUNKER), the International Convention on Salvage 1989)  could accommodate the concept of MASS, although in some cases interpretations or amendments might be required. These include:

  • The role and the responsibility of the master/remote operator and especially the division of tasks between them;
  • Questions of liability, and notions such as negligence/fault/recklessness might not be applicable, issues of causation might be more difficult to prove, while the determination personal fault of the shipowner/carrier and vicarious liability/third party liability would have to be re-thought under the prism of national law;
  • Certification required under the conventions might have to be reconsidered, especially in Degrees Three and Four where there is no seafarer onboard.

The LEG also highlighted that conventions that are not under the auspices of the IMO, such as UNCLOS and the MLC 2006, might have to consider any future work of the IMO on MASS.

Finally, the FAL Committee[7] , which supervises the implementation of the Convention on Facilitation of International Maritime Traffic was in agreement with most of the conclusions of the MSC and LEG relating to the need for definitions and clarifications of certain terms in the context of the FAL Convention. It also highlighted that consideration should be given to situations such as the discovery of stowaways and the accommodation of people rescued at sea and refugees. It also emphasized that effective information exchange with the introduction of MASS might require machine-readable and decentralized format based on open and interoperable interfaces to enable automated processes.

The way forward

With the finalization of the scoping exercise, and after the agreement of all three engaged committees[8],  in April 2022, MSC 105 designed a roadmap[9]  to develop a non-mandatory goal-based MASS Code with a view to adoption in the second half of 2024. Based on the experience gained in its application, a mandatory MASS Code might follow, which would enter into force on 1 January 2028.  The IMO also organized, in September 2022 an online Seminar on Development of a Regulatory Framework for MASS with broad participation of researchers, academia, the private sector and IMO Member States to explore the subject and facilitate the lifting of certain regulatory obstacles. 

In addition to the above, a Joint MSC-LEG-FAL Working Group was established as a cross-cutting mechanism to address common high-priority issues identified by the regulatory scoping exercises conducted by the three committees.  To date, the first session the MSC-LEG-FAL Joint Working Group[10] that took place on September 2022 considered issues perceived as high priority by all three Committees, namely:

  • The definition of the term “master”, its role and responsibilities
  • The role and competences of the crew of a MASS (and its potential designation of its status as seafarer).
  • The definition of “remote control station/center” and its requirements
  • The definition of the term “remote operator”, its responsibilities, required competencies and status as a seafarer.

No decisions were reached in the group, but a template was created for the participating Member States to identify and collect information of options for interpretations in view of the next meeting, which is scheduled to take place sometime in 2023 according to the approved roadmap. It was also agreed by the Joint Working Group to organize another seminar, this time on legal issues including UNCLOS, back-to-back with the next MASS-JWG meeting [11].

Thus, important work on the legal framework to accommodate MASS is ongoing at the IMO. The outcome would hopefully provide for much-needed legal certainty in matters related to the safe and secure operation of automated vessels and would undeniably spur more legislative change both in other international fora as well as at national levels. Developing countries and seafarers’ associations should take advantage of the opportunity to have their voice heard at this key juncture and consider becoming actively involved in this important ongoing work.

[1] See for instance Advanced Autonomous Waterborne Applications Initiative (AAWA) (2016). Remote and Autonomous Ships - The next steps.

[2] Of course reduction does not mean elimination, as human error is also present in on-shore aspects of automation, see Ramos, MA, Bouwer Utne I, Mosleh A. (2019) Collision avoidance on maritime autonomous surface ships: Operators’ tasks and human failure events .

[3] As has been noted, a recurring and common weakness with technological innovation is that accompanying systems  (including their legal frameworks) for its safe and secure use may not give sufficient consideration to the intersection with factors such as security (e.g., terrorism, organised crime, piracy, cyber/radio frequency/satellite attacks, drone strikes, holding to ransom, diversion of sensitive cargo to hostile actors) and disaster risk management (e.g., resultant collisions, pollution, loss of business continuity, search and rescue of crew, disaster impacts, etc). Global Security and Disaster Management (2019) Maritime Autonomous Ships (MASS) and Framework Development Changes.

[4] See Li S and Fung KS, Maritime autonomous surface ships (MASS): implementation and legal issues (2019) Vol 4 Maritime Business Review 335, noting that in Hong Kong the operation of such vessels would only be permitted if they can comply with local rules and regulations.

[5] Out of the 2,136,190 vessels globally, 1,726,903 fly a developing state flag.

[6] According to estimates of national contributions to the current global supply of seafarers, the Philippines, China, India, Ukraine and Russia alone account for 44% of the global seafarer workforce supply. See also 2021 ICS BIMCO Seafarers Workforce Report.

[7] FAL.5/Circ.49  Available at .

[8] LEG 109/16/1, paragraph 13.14, MSC 105/20, paragraph 7.27 and FAL 46/24, paragraph 14.17.  Available at

[9] MSC 105/7. Available at

[10] MSC 106/5. Available at

[11]Ibid, para 12.


Argyro Kepesidi | Associate Legal Officer, Policy and Legislation Section, Trade Logistics Branch, UNCTAD |

The views and opinions expressed in this article are those of the authors and do not necessarily reflect the views of the United Nations Secretariat.
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