AI Regulation Tracker  /  Standards and safety

IMO Adopts the First Global Code for Remotely Operated and AI-Enabled Ships

Non-mandatory from July 1, 2026; a mandatory MASS Code is targeted around 2032. On May 22, 2026, the International Maritime Organization adopted the MASS Code, the first international goal-based safety framework for Maritime Autonomous Surface Ships. It took effect July 1, 2026, but as a non-mandatory, experience-building instrument. A mandatory version is being developed for later this decade.

By Anthony Guerriero  ·  The Leveraged Years Regulatory Research  ·  Published July 19, 2026  ·  Last updated July 19, 2026

The IMO has done something it has never done before. On May 22, 2026, at the close of the 111th session of its Maritime Safety Committee, it adopted a dedicated Code for Maritime Autonomous Surface Ships, known as MASS. The instrument is Resolution MSC.595(111), and it took effect on July 1, 2026. For an industry that has been running pilots and one-off approvals for years with no common rulebook, this is the first time there is a single international framework written specifically for ships that are controlled from shore or that operate with a high degree of automation and AI in the loop.

The IMO describes the framework in plain terms. In its own words, the MASS Code "sets out a comprehensive, goal-based framework to ensure that remotely controlled or autonomous ships are designed and operated to a level of safety, security and environmental protection that is expected of a conventional ship." Goal-based is the operative phrase. Rather than prescribing exactly how to build the ship, the Code sets the safety outcomes a MASS has to achieve and leaves builders and operators to demonstrate they meet them. That is the same regulatory style the IMO has moved toward for conventional tonnage, and it is the sensible approach when the technology is moving faster than any prescriptive rule could keep up with.

What the Code actually covers

The MASS Code is broad. It reaches across navigation, the remote operations centres from which shore-based crews control or supervise these ships, cybersecurity, system design, fire safety, search and rescue, and risk assessment. In other words, it does not just address the software that steers the vessel. It addresses the whole operating system around an autonomous ship, including the physical and human infrastructure ashore that a remotely operated vessel depends on. The remote operations centre is treated as part of the safety envelope, not as an afterthought, which matters because the centre and its connectivity are exactly where a remotely operated ship is most exposed.

The human element runs through all of it. The Code is explicit that automation does not dissolve responsibility. The IMO states that it "underscores the importance of human oversight, with the master retaining overall responsibility for the ship at all times." Read that carefully, because it settles a question that has hung over autonomous shipping from the start. Even when the master is not physically on board, the master still carries overall responsibility for the vessel. The Code does not create a category of ship where no accountable human is in charge. It relocates the human, it does not remove them, and that framing is going to shape how liability gets argued for years.

Read the status precisely: this is not mandatory yet

Here is the part that gets lost in the headlines, so I want to be exact about it. The MASS Code has been adopted and it is in effect, but it is non-mandatory. It is a voluntary, goal-based Code that opens what the IMO calls an experience-building phase. During this phase, administrations and operators that choose to apply the Code do so voluntarily, and they feed operational data, formats, and lessons back to the IMO. That accumulated experience is meant to inform a mandatory MASS Code, which the IMO is developing on a separate track and which is targeted to enter into force no earlier than January 1, 2032.

So there are two things happening at once, and it is worth keeping them apart. There is a real, adopted, in-force framework you can align to today, and there is a future binding instrument that does not exist yet and will not for years. Anyone telling you that autonomous ships are now "regulated" in a mandatory sense is overstating it. Anyone telling you nothing has changed is missing that the reference standard the entire sector will be judged against is now written down and agreed. Both errors are easy to make. The accurate read is that the rules of the road for autonomous shipping have a first draft, and it is the one that counts.

Why this matters even though it is voluntary

A non-mandatory Code still moves the market. Class societies will build their certification services around it. Flag administrations that want to attract autonomous tonnage will implement it. Insurers will ask whether your operation aligns with it before they price the risk. Port states will look to it when a remotely operated ship shows up in their waters. In practice, a voluntary international framework of this kind tends to become the de facto standard well before it becomes a legal one, because everyone in the chain prefers to be measured against the same yardstick. The experience-building phase is also where the operators who participate get to shape the mandatory Code that follows. Sitting it out is a choice to let others write the rules you will eventually have to live under.

What this means for US owners, operators, and counsel

For the United States specifically, a few things are worth holding in view. The IMO framework does not self-execute in US law. It works through flag and port state administrations, which means the United States Coast Guard is the body that will decide how, and how far, to give the MASS Code effect for US-flag tonnage and for foreign autonomous ships calling at US ports. US-flag operators exploring autonomous or remotely operated vessels should expect the Coast Guard to lean on this Code as the international reference point, and should be building their safety cases so they map cleanly onto its goal-based structure rather than to a bespoke standard of their own.

For US owners and operators, the practical move now is governance, not paperwork panic. Document how your remote operations centre is staffed, secured, and supervised. Be able to name the master who retains overall responsibility for each vessel and show the chain of authority from shore to ship. Treat cybersecurity of the shore-to-ship link as a safety issue, because the Code does. For maritime counsel, this is the moment to read the Code closely against your clients' existing charter parties, insurance wordings, and liability allocations, since the Code's insistence that a master retains responsibility even when ashore will interact with how fault and limitation get argued when something goes wrong. None of this is compelled today. All of it is cheaper to do now, while the standard is voluntary, than after a mandatory Code and a casualty have made the questions concrete.

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Informational analysis for working professionals, not legal advice. Confirm how any code or requirement applies to your situation with qualified maritime counsel in the relevant jurisdiction.