The Poseidon Principles for Marine Insurance were developed later (December 2021) and were strongly inspired by the Poseidon Principles. The four core Principles are the same for both the Poseidon Principles and the Poseidon Principles for Marine Insurance and both initiatives also use the same metric – AER (Annual Efficiency Ratio). The Poseidon Principles for Marine Insurance, however, have also chosen to take steps toward alignment with the Paris Agreement by providing two trajectories: a 50% CO₂ reduction trajectory in alignment with the 2018 IMO GHG Strategy and a 100% CO₂ reduction trajectory. They have also committed to updating current trajectories in 2024 to align with the 2023 IMO GHG Strategy.
Another initiative similar to the Poseidon Principles is the Sea Cargo Charter – a framework for responsible chartering. The ambition to develop the Sea Cargo Charter finds its source is the early stages of the Poseidon Principles. The four core Principles are the same for both the Poseidon Principles and the Sea Cargo Charter, but the two frameworks rely on different metrics. The Poseidon Principles uses AER and can therefore rely on the IMO DCS to collect data, while the Sea Cargo Charter uses EEOI and thus have a different approach to source data.