The IMO (International Maritime Organisation) is the United Nations’ specialised agency with responsibility for the safety and security of shipping and the prevention of marine and atmospheric pollution by ships.

The IMO approved an initial greenhouse gas (GHG) strategy in April 2018 to reduce GHG emissions generated by shipping activity, prescribing that international shipping must reduce its total annual emissions by at least 50% of 2008 levels by 2050, whilst pursuing efforts towards phasing them out as soon as possible in this century. Following the 2018 GHG Strategy, the IMO approved a revised strategy on the reduction of GHG emissions from ships in July 2023.

This 2023 IMO GHG Strategy sets out the following levels of ambition:

1. to reduce the total annual GHG emissions from international shipping by at least 20%, striving for 30%, by 2030, compared to 2008
2. to reduce the total annual GHG emissions from international shipping by at least 70%, striving for 80%, by 2040, compared to 2008.
3. GHG emissions from international shipping to peak as soon as possible and to reach net-zero GHG emissions by or around, i.e. close to 2050

Further terms that do not define GHG reduction rates, but are also in the revised level of ambition include:

4. carbon intensity of the ship to decline through further improvement of the energy efficiency for new ships
5. carbon intensity of international shipping to decline to reduce CO2 emissions per transport work, as an average across international shipping, by at least 40% by 2030, compared to 2008
6. uptake of zero or near-zero GHG emission technologies to represent at least 5%, striving for 10%, of the energy used by international shipping by 2030

Moreover, any activity related to emission reduction and climate alignment in shipping will need to capture lifecycle emissions (well-to-wake approach) as well as all the relevant GHG species as specified by the IMO.

The strategy also states that a basket of antedate measure(s), delivering on the reduction targets, should be developed to promote the energy transition of shipping and provide the world fleet a needed incentive while contributing to a level playing field and a just and equitable transition.

According to the IMO’s Fourth GHG Study 2020, the sector accounted in 2018 for 2.89% of global anthropogenic emissions. Left unchecked, shipping emissions were expected to grow by 90-130% by 2050 compared to 2008 levels.

While CO₂ represented almost all of the industry’s GHG emissions (98%), methane (CH₄) emissions from ships increased over this period (particularly over 2009–2012) due to increased activity associated with the transport of gaseous cargoes by liquefied gas tankers due to methane slip. There is potential for this trend to continue in the future if shipping moves to liquefied natural gas (LNG)-powered ships.

Nations pledged in the 2015 Paris Agreement “to achieve a balance between anthropogenic emissions by sources and removals by sinks of GHG in the second half of this century” (UNFCC, 2015). This means getting to “net zero emissions” between 2050 and 2100. 2050 therefore represents a key milestone in the Paris Agreement, which the IMO explicitly references in its Strategy. The Intergovernmental Panel on Climate Change (IPCC) has quantified this target through a specific limit to a global temperature rise due to anthropogenic emissions of not more than 1.5°C compared to pre-industrial levels.

The 2023 IMO GHG Strategy does not alone secure 1.5°C future.

The objective of the Poseidon Principles for Marine Insurance is to use the knowledge on portfolio climate alignment to support marine insurance clients in the transition to net zero journey, enhancing transparency. They aim to be voluntary, practical to implement, verifiable, fact-based, and effective. Signatories commit to implementing the Principles in their internal policies, procedures and standards.

The Principles are intended to evolve over time following a regular review process to ensure that they are practical and effective, are linked to and support the IMO’s GHG measures developed overtime, and that further environmental factors are identified for inclusion.

The Poseidon Principles for Marine Insurance offer a framework for insurers to assess and disclose the climate alignment of their hull and machinery (H&M) portfolios.

H&M represents the second largest part of marine insurance coverage (with Marine Cargo as the largest portion), which means this first step offers the greatest coverage and potential for impact across Marine Insurance. In terms of data availability to measure carbon emissions, H&M offers a comparable starting point to the Poseidon Principles for Financial Institutions as a tangible first step to assess and disclose climate alignment. 

By following the framework and common baseline, climate alignment data is available for signatories to better enable the alignment of their portfolios with responsible environmental impacts.

Climate alignment is currently the only environmental factor considered by the Poseidon Principles for Marine Insurance. This scope will be reviewed and may be expanded by signatories on a timeline that is at their discretion.

The Poseidon Principles for Marine Insurance were developed in an effort spearheaded by global shipping insurers, leading industry players (brokers, shipowners and classification societies) as well as the Global Maritime Forum, Swiss Re Corporate Solutions, and UMAS. The drafting group included Gard, Cefor, Willis Towers Watson, Mærsk, Star Bulk, and Lloyd’s Register. The International Union of Marine Insurers (IUMI) was regularly consulted.

The Poseidon Principles for Marine Insurance were developed with the involvement of shipowners. This was to ensure that the Principles were developed and shaped in a way that considered the shipowner perspective as the clients of the signatories and affiliate members. How the Principles will affect clients was prioritised throughout the process, to ensure that shipowners are supported in the best way.

The Global Maritime Forum and UMAS have been part of this work since its inception. They have also been working with other initiatives such as the Poseidon Principles for Financial Institutions and the Sea Cargo Charter, to ensure that various initiatives within the shipping sector are compatible. A broader group of NGOs and other stakeholders have been kept informed throughout the process, like the UNEPFI as well as IUMI.

The Poseidon Principles for Marine Insurance were developed in December 2021 and were strongly inspired by the Poseidon Principles (for financial institutions). The four core Principles are the same for both initiatives, which also use the same metric, the AER (Annual Efficiency Ratio).

Another similar initiative is the Sea Cargo Charter, a framework for responsible chartering. The ambition to develop the Sea Cargo Charter finds its source in the early stages of the Poseidon Principles. The four core Principles are the same for all three initiatives, but the Sea Cargo Charter uses the EEOI (Energy Efficiency Operational Indicator) as an emission intensity metric due to their unique ability to access the necessary data. 

Institutions wishing to become a signatory or affiliate member must submit three documents to the the Secretariat of the Poseidon Principles for Marine Insurance: the Standard Declaration, the Application, and the Membership Agreement. Once accepted into the Association, the new member will have five months to complete and submit the Self-Assessment to the Secretariat. All documents are available from the Secretariat.

The Standard Declaration for Signatories is the formal commitment required of an insurance provider to become a signatory. The Standard Declaration announces the intention of the insurance provider to follow all binding requirements of the Poseidon Principles for Marine Insurance. This means that the insurance provider is prepared to take the necessary steps to comply with all four Principles, and have made this commitment and related reporting public.

The Standard Declaration for Affiliate Members is the formal commitment required for an institution wishing to become an affiliate member of the Poseidon Principles for Marine Insurance. It announces the public support of the initiative and prepares the institution for supporting signatories and the implementation of the Principles. There is one declaration for all organisations: brokers, P&I Clubs, captives, etc.

The Signatory Membership Agreement is the formal agreement between the insurer and the Poseidon Principles for Marine Insurance Association for the institution to become a signatory and a member of the Association. By signing the membership agreement, the signatory agrees to abide by the Governance Rules of the Association.

The Affiliate Membership Agreement is the formal agreement between the organisation and the Poseidon Principles for Marine Insurance Association for the institution to become an affiliate member of the Association. By signing the membership agreement, the affiliate member agrees to abide by the Governance Rules of the Association.

Each new signatory has five months to complete the Signatory Self-Assessment and return it to the Secretariat. New affiliate members also have five months to complete the Affiliate Member Self-Assessment and return it to the Secretariat.

The purpose of this is to ensure that each signatory and affilite member has made appropriate arrangements to fulfil its obligations under the Poseidon Principles for Marine Insurance and identified any challenges to doing so. The Self-Assessment is as brief as possible to reduce the administrative burden, while still addressing the core responsibilities of signatories and affiliate members. The questions focus on ensuring that signatories and affiliate members are aware of timelines and obligations under the Poseidon Principles for Marine Insurance, have engaged internal stakeholders, have engaged clients and have a plan for engaging the necessary service providers so that they can complete the disclosure requirements.

The Poseidon Principles for Marine Insurance are designed to support other sustainable insurance initiatives. They are aligned with the Poseidon Principles for Financial Institutions and the Sea Cargo Charter, and are also intended to support other initiatives, such as the Carbon Disclosure Project (CDP), the Task Force on Climate-related Financial Disclosure (TCFD) and the UNEPFI Principles for Sustainable Insurance (UNEP PSI).

The Principles support the transition of global shipping, as well as the work of the Partnership for Carbon Accounting Financials (PCAF). As such, the Principles set a pioneering framework for reporting emissions for the shipping industry, thus enhancing accountability and transparency and creating a global baseline to support and work towards the greater climate goals.

1. Meet the increasing demands for transparency and show support for IMO climate ambitions through disclosure of climate alignment
2. Join a community of action and like-minded organisations with expert support
3. Support clients in their decarbonisation journey based on robust data & strengthen your value proposition
4. Play a leadership role in climate mitigation for the benefit of current and future generations
5. Act proactively to be prepared for compliance and build an understanding of de-risking the net zero transition

The Poseidon Principles for Marine Insurance were developed in recognition of the insurance industry’s role in promoting responsible environmental stewardship throughout the maritime value chain. Signatories are recognised for contributing to an initiative that is ground-breaking in the spheres of shipping and insurance. Furthermore, signatories gain access to like-minded network of organisations and valuable data that can be used to assess and mitigate potential climate risks.

The sign-on fee for 2025 is €12,000 and is paid to the Poseidon Principles Association when becoming a signatory or affiliate member. This is paid only one time upon joining. The annual fee for 2025 is € 14,000 for signatories and € 9,000 for affiliate members. It is paid annually to the Poseidon Principles Association in accordance to the Governance Rules. 

In the first year of membership, the annual fee is required in addition to the sign-on fee. 

Fees are subject to approval by all signatories and affiliate members at the Annual Meeting each year.

In shipping, or emissions intensity represents the total emissions generated to complete one unit of transport work, which is measured in grams of CO₂e per ton-nautical miles. For the Poseidon Principles for Marine Insurance, this is measured using a carbon equivalent intensity measure known as Annual Efficiency Ratio (AER), which is reported in unit grams of CO₂e per dwt-nm (gCO₂e/dwt-nm). The IMO DCS enables the calculation of the AER, thus ensuring that the Poseidon Principles for Marine Insurance are consistent with the IMO’s regulations.

The AER requires the following data to be calculated:

• fuel consumption by fuel type in metric tonnes,
• distance travelled in nautical miles,
• DWT at summer draught.

This data is identical with what shipowners submit to the IMO DCS which means that there is no extra burden on the clients in matter of acquiring the data. As of May 2025, all signatories will use modelled data when calculating climate alignment in lieu of IMO DCS data.

The Poseidon Principles for Marine Insurance uses continuous required emission intensity baselines for each vessel type. The emissions intensities of individual ship types are estimated based on the mean AER values from the Fourth IMO GHG Study. More information can be found in the Technical Guidance. 

In the context of the Poseidon Principles for Marine Insurance, a decarbonisation trajectory is a representation of how many grams of CO2e a single ship can emit to move one metric tonne of goods one nautical mile on a well-to-wake basis (gCO2e/tnm) over a given time to be in line with the 2023 IMO GHG Strategy ambition of reducing total annual well-to-wake GHG emissions to net-zero around 2050.

The Poseidon Principles for Marine Insurance uses two decabonisation trajectoires to fully align with the 2023 IMO GHG Strategy: 

1. 2023 IMO GHG Strategy – Minimum: Represents the IMO 2023 GHG “minimum” indicative checkpoint of reducing emissions from international shipping by 20% in 2030 and 70% in 2040 relative to 2008, then reaching net zero by 2050. 
2. 2023 IMO GHG Strategy – Striving: Represents the IMO 2023 GHG “striving” indicative checkpoint of reducing emissions from international shipping by 30% in 2030 and 80% in 2040 relative to 2008, then reaching net zero by 2050.

Both of these trajectories include all GHG species and well-to-wake emissions. The trajectories will be reviewed and improved over time to maintain the robust nature of the initiative and remain in step with up to date climate science and goals.

The Secretariat and Advisory of the Poseidon Principles for Marine Insurance Association will produce and provide standard decarbonisation trajectories for each ship type for signatories based on agreed-upon and clearly stated assumptions. The decarbonisation trajectories are produced for each ship type in a format that allows for portfolio aggregation to ensure climate alignment is practical, straightforward, and comparable between signatories. More information can be found in the Technical Guidance.

Upon analysis of the impact of MEPC 80, the GHG reduction levels used to define the new 2023 IMO ambition aligned trajectories are quite close to the 1.5ºC pathway for shipping. Because of this similarity, the Poseidon Principles for Marine Insurance has decided to concentrate on incorporating the forward-looking IMO revised strategy and postponed introducing an additional trajectory aligned with a 1.5°C future for this reporting cycle.

While this means that the trajectories used to measure climate alignment in this report are not aligned with a 1.5ºC temperature goal, using trajectories which represent the 2023 IMO GHG Strategy is still a significant step toward aligning with the Paris Agreement.

The methodology that underpins the Poseidon Principles for Marine Insurance has been carefully designed to ensure that no type or size of vessel is disadvantaged. Thus, it does not matter which types or sizes of vessel are in a hull and machinery portfolio; what matters is the emission intensity of those vessels relative to their respective decarbonisation trajectories.

There is no publicly available data for this calendar year which would allow climate alignment to be calculated per ship type or size, so there is some uncertainty on whether current portfolios are likely to be aligned with the trajectory. It is expected that the median emission intensity by ship type and size will not be far from today’s trajectory alignment requirements, in large part because the fleet has seen significant emission intensity improvement (slow steaming, increase in attention on energy efficiency, new build EEDI regulation) since 2008. Historical data shows some variation within each ship type and size, so depending on the mix of ships in a given insurer’s portfolio this may not be the case. If results from the first year of reporting show that there is a systemic (across signatories’ portfolios) significant misalignment, there is scope to revise the assumptions underpinning the trajectories. Likewise, the trajectories will be updated as more accurate data becomes available (e.g. EU MRV data, new IMO GHG Study, and any analysis presented by the IMO).

The Poseidon Principles for Marine Insurance establish a framework for the assessment of climate alignment and disclosure of hull and machinery portfolios. It does not provide solutions for how to achieve climate alignment. It is the responsibility of signatories to determine how they choose to improve their portfolio performance.

Broadly speaking, however, to improve a portfolio’s score, it is necessary to reduce the emission intensity of the vessels that underlie the portfolio relative to their respective decarbonisation trajectory. In the short- to medium-term (1-5 years), for most sectors, especially for ships which travel on long haul routes, the most commercially viable solutions for reducing emission intensity are through speed reduction and energy efficient technologies and operation scheme. Over the long-term (in 10+ years), the sector will need to use increasing quantities of energy and fuel which produce lower GHG emissions when used on board. Options include harvesting of renewable energy on board (wind propulsion, solar, wave), bioenergy, battery energy storage, synthetic or e-fuels (sometimes also called power-to-liquid or power-to-gas), made from renewable electricity or fossil fuel sources in combination with carbon capture and storage (CCS).

These options are at varying levels of readiness and use. For example, solar has been in use for supplementing auxiliary power for some time. Wind assistance technologies have been in use for some time on several sea going ships, as has battery energy storage and biofuel. Some of these options have yet to be deployed for deep sea shipping operation (for example bioenergy and synthetic/e-fuels) but are already deployed and in operation for short sea shipping. Their application for deep sea shipping use is the subject of intense R&D effort, and their potential availability is expected over the coming decade.

Signatories and affiliate members can engage with clients to identify ways to bring down emissions intensity or they could rebalance their shipping portfolio over time towards parts of the sector that are more climate-aligned or towards technologies that are climate-aligned (e.g., lower-carbon fuels).

As of May 2025, all signatories use modelled data when calculating climate alignment in lieu of collecting IMO DCS data. The data is sourced from a recommended third party that has been validated by the Technical Committee through a benchmarking exercise. The exercise was also reviewed and validated by the Nordic Association of Marine Insurers (Cefor).

Being a signatory to the Poseidon Principles for Marine Insurance does not preclude the use of carbon offsetting, but these are not considered when reporting emissions and assessing climate alignment under the methodology: the full extent of emissions is captured in the assessment of climate alignment.

Different fuels emit different amounts of different GHG’s according to their chemical composition. This combines with the efficiency of the vessel’s operation to determine the emission intensity of voyages. The emission factors to be used can be found in the Technical Guidance. It should be noted that low sulphur variants carry the same GHG emission factor as high sulphur equivalents.

The current regime for GHG accountability is increasingly includes a lifecycle approach to assess the emissions associated with specific fuels. This implies that upstream emissions (emissions from the extraction, cultivation, processing and transportation of fuels before reaching a vessel’s bunker) will play an increasingly important role in decision-making around long lifetime assets such as ships which require an energy source to operate.

While the initial IMO GHG Strategy in 2018 considered operational emissions (tank-to-wake approach), the 2023 IMO GHG Strategy captures lifecycle emissions (well-to-wake approach). The most pertinent to determine upstream emissions for the purposes of the maritime industry is the lifecycle assessment (LCA) guidance, that is due to be finalised in 2024. These LCA guidelines will provide a widely accepted framework for defining emission factors which are expected to become the standard for the industry.

As the Poseidon Principles for Marine Insurance wait for the distribution of these guidelines, a set of interim emission factors has been developed in the meantime by the Technical Advisory to be able to fully align with the ambition in the 2023 IMO GHG Strategy in the interim period. Main sources used were the provisional IMO LCA Guidelines, material from the European Commission outlining reporting under Fit for 55 regulation, the Fuel EU/ecoinvent database, as well as the GREET framework used in the US.  Emission factors for conventional liquid fuels are also available in MEPC 80/7/4.

Any improvements undertaken by the owner in terms of efficiency (design or operational) will be reflected in the fuel consumption and hence in the data/score.

Much like other operational efficiency measures, this will result in reduced fuel consumption and hence be reflected in the data/score of the vessel.

Older vessels may have a higher fuel consumption, which in turn would be reflected in the vessel’s AER.

Yes. The initial IMO GHG Strategy considered only operational emissions (tank-to-wake approach) while the 2023 IMO GHG Strategy captures lifecycle emissions (well-to-wake approach). This approach comprehensively measures a ship’s total emissions, upstream and operational emissions, which prevents issues arising from emissions “leakage” due to fuels which have zero carbon emissions on a tank-to-wake basis but higher emissions when their upstream emissions are counted.

Reporting in a well-to-wake perspective requires the use of emission factors that cover the impact of the whole life cycle of the fuel as well as the relevant GHG species (carbon dioxide, methane, and nitrous oxide). Interim emission factors have been developed by the Poseidon Principle’s Advisory to be able to fully align with the ambition in the 2023 IMO GHG Strategy in the interim period before the publication by the IMO of updated lifecycle assessment (LCA) guidance.

The main sources used were the provisional IMO LCA Guidelines, material from the European Commission outlining reporting under Fit for 55 regulation, the Fuel EU/ecoinvent database, as well as the GREET framework used in the US.  Emission factors for conventional liquid fuels are also available in MEPC 80/7/4.

With this information at hand and keeping the logic that transparency will be key to ensure legitimacy and credibility for any pragmatic way forward, the following cascading order of emission factor priority has been adopted:

1. Emission factors for conventional liquid fuels available in MEPC 80/7/4 should be used;
2. All other emission factors should be taken from the Fuel EU/ecoinvent database.
3. Any other emission factors should be taken from the GREET database.

A complete list of emission factors can be found in the Technical Guidance.

Yes. It is the same as used in other IMO regulatory mechanisms (e.g., EEDI).

As of May 2025, signatories will use modelled data when calculating climate alignment in lieu of collecting IMO DCS data.

The Modelled Data Pathway Track uses estimations of vessel information to produce climate alignment scores. This differs from the processes used in the last two years, which involved signatories gathering measured IMO DCS data from their clients. The first three steps of the information flow process used by signatories were the most impacted by the Modelled Data Pathway. Allowing signatories to source vessel data, vessel climate alignment scores, and the overall portfolio climate alignment scores from a third-party data provider has helped to reduce some of the administrative burden they have faced, and enabled them to collect and report data on timelines that work best for their internal processes. It also provided an efficient way to gather climate data on the entire H&M portfolio and calculate climate alignment in minutes.

Learnings from the first reporting process, which included the Modelled Data Pathway for the first time in 2025, will be assessed and used to inform possible future refinements to the information flow pathways.

An external audit is not a requirement of the Poseidon Principles for Marine Insurance. However, in practice, some insurance providers will choose to have an independent assessment in line with their other reporting activities.

Signatories to the Poseidon Principles for Marine Insurance are expected to comply with the Accountability and Transparency requirements listed in the Technical Guidance. The Secretairt reviews all disclosure information, and certain information will be shared privately to other signatories as well as the Advsiory to ensure accuracy.

Due to the reliance on modelled data, the standard covenant clause is no longer required. This also means there are no longer any data-sharing requirements between signatory claims leaders and followers since signatories will no longer request data from clients.

Instead, all signatories are encouraged to rely exclusively on the recommended data provider to source validated information.

Signatories evaluate the specific information required for reporting each year and submit it using the Signatory Reporting Template or the Affiliate Member Reporting Template, which is available from the Secretariat. Some information is publicly disclosed, and other information is only disclosed internally to other signatories to inform the actions of the Steering Committee. More information is available in the Technical Guidance.

Every effort has been made to minimise the reporting requirements of the Poseidon Principles for Marine Insurance themselves. While it is required that signatories include their portfolio climate alignment figure in relevant institutional reports (e.g., sustainability reports), the Poseidon Principles for Marine Insurance do not interact with any other reporting initiatives.

The Poseidon Principles for Marine Insurance will publish the portfolio climate alignment scores of signatories on its website, in the Annual Disclosure Report where the Association will also provide some context in order to put the scores alignment score in perspective and correctly interpret them. The previous reports can be found on the Resources page.

Signatories are required to publish their portfolio climate alignment in relevant institutional reports (e.g., sustainability report) on timeline that is appropriate for them. There is however nothing to stop individual signatories to publish their climate alignment at a more granular level, for example by vessels category.

Steering Committee: The Steering Committee is comprised of 8 to 12 representatives of signatories to the Poseidon Principles for Marine Insurance. One member acts as Chair, one member as Vice Chair, one member as Treasurer. Steering Committee members hold a senior position in their companies relevant for the Poseidon Principles for Marine Insurance. The Steering Committee leads the Association’s meetings. Members of the Steering Committee are volunteers and are therefore not compensated by the Association. The list of members currently part of the Steering Committee can be found on the website

Signatories/affiliate members: All signatories/affiliate members are members of the Poseidon Principles for Marine Insurance Association and are encouraged to participate in and contribute to the management of the association in a manner that supports the Principles and is appropriate for their institution. Those institutions who have become signatories/affiliate members will appoint a senior representative to join relevant meetings of the association, such as the Annual Meeting. Just as with the Steering Committee, the representative must hold a position relevant to the Poseidon Principles for Marine Insurance. Signatories can nominate a representative from their institution to become a member of the Steering Committee. Nominees are then voted into positions by all signatories and serve a term in the Steering Committee as outlined in the Governance Rules.

Technical Committee: Signatories previously agreed to establish the Technical Committee. Its role is to ensure methodological integrity of the Poseidon Principles for Marine Insurance within the scope agreed by the Steering Committee. The Technical Committee does not have decision-making power; it formulates proposals which are then brought up to signatories. The Technical Committee is composed of a subset of signatories and is supported by the Advisory and Secretariat. Technical Committee members must hold appropriate technical background.

Secretariat: The role of the Secretariat is to maintain the day-to-day business and administration of the Steering Committee, the Principles, and the signatories/affiliate members. The Secretariat serves a facilitating function in the Steering Committee, Technical Committee, and among members. The Secretariat role can be fulfilled by a relevant non-profit and independent third-party entity. This role is currently fulfilled by the Global Maritime Forum.

Advisory: The advisory advises and guides the technical discussions and expertise of the Principles, including creating and revising the scope of the Principles or the decarbonisation trajectory. It ensures the used methodology and data found in the Principles are current, relevant, and simple to implement for signatories. The advisory is also involved in working groups and takes part in the Steering Committee or Technical Committee meetings as needed. Current technical advisory is UMAS.