⚖️Current legal status overview
1
Status of MEPC 83
Draft text approved — not yet formally adopted or in force. The IMO Net-Zero Framework is included in draft language for a new MARPOL Annex VI chapter.
2
Status of MEPC/ES.2
Adoption was scheduled for October 2025, but the session was suspended and postponed; negotiations continue in 2026.
3
How to describe entry into force
Do not state a fixed entry-into-force date yet. Correct wording: after formal adoption, entry into force is expected about 16 months later under tacit acceptance.
Key takeaway: The IMO Net-Zero Framework remains at the “draft approved, pending formal adoption” stage. Any 2027 or 2028 implementation timelines depend on subsequent IMO adoption and entry-into-force arrangements.
📝MEPC 83 and MEPC 84 session highlights
MEPC 83 | 7–11 April 2025
Draft approved MARPOL Annex VI- Approved the IMO Net-Zero Framework draft as the legal basis for a new MARPOL Annex VI chapter.
- Mid-term GHG measures centre on two pillars: a global fuel standard and a global GHG pricing mechanism.
- Completed Phase 1 review of short-term GHG measures and set CII reduction factors through 2030.
- Approved expanded availability and transparency of IMO DCS fuel consumption data.
- Advanced work on LCA, sustainable fuel certification, OCCS, and non-CO₂ GHG measurement.
MEPC 84 | 27 April – 1 May 2026
Ongoing negotiations Guidance advanced- No final compromise on the IMO Net-Zero Framework; discussions continue at two ISWG-GHG meetings before MEPC 85.
- MEPC 85 is tentatively scheduled for 30 November – 3 December 2026; MEPC/ES.2 is tentatively planned to resume on 4 December 2026, subject to MEPC 85 confirmation.
- Launched the Phase 2 review of SEEMP and CII, targeted for completion in 2028.
- Cruise ship cgHRS and adverse-weather CII metrics remain unsettled.
- Terms of reference for the fifth IMO GHG study were finalised, expected to support the 2028 GHG strategy review.
🌍IMO Net-Zero Framework and GFI
Scope of application
Applies to: ocean-going / international voyaging ships above 5,000 GT — covering the main emission sources in international shipping.
Currently excluded or deferred
- Ships below 5,000 GT are not in scope now; expansion to 400–5,000 GT ships may be discussed later.
- Non-mechanically propelled ships are not covered.
- Platform-type units such as FPSOs, FSUs, and drilling rigs are excluded regardless of propulsion.
- Semi-submersibles are deferred pending further review.
GFI definition
GHG Fuel Intensity (GFI) measures the lifecycle emission intensity of fuels and energy used by a ship.
GFI = Σ(EIj × Energyj) ÷ Energytotal
Unit: gCO₂eq/MJ; Well-to-Wake lifecycle methodology.
- EIj: GHG emission intensity of energy source j.
- Energyj: Energy consumed from source j in the reporting period.
- Energytotal: Total annual energy consumption.
- Covers CO₂, CH₄, and N₂O, expressed as CO₂ equivalent.
GFI targets and baseline
GFIT = (1 − ZT ÷ 100) × GFI2008
GFI2008 = 93.3 gCO₂eq/MJ; ZT is the reduction percentage for year T.
Base Target: baseline compliance threshold at a higher GFI level.
Direct Compliance Target: stricter than the Base Target; performance below this level can generate surplus units.
⚙️Compliance balance, surplus units, and remedial mechanisms
Compliance balance formula
Compliance Balance = (Direct Compliance Target GFI − Attained Annual GFI) × Energytotal
- Positive result: below the Direct Compliance Target — can generate Surplus Units.
- Negative result: above the Direct Compliance Target — deficit must be remedied.
- Surplus units are expressed in tonnes CO₂eq and may be retained, transferred, or cancelled; each unit can only be used once.
Deficit remedy logic
| Attained GFI position | Compliance outcome | Remedy |
|---|---|---|
| Below Direct Compliance Target | Surplus | Eligible for Surplus Units |
| Between Direct Compliance Target and Base Target | Tier 1 deficit | Remedy Tier 1 Deficit |
| Above Base Target | Tier 2 deficit | Remedy Tier 1 + Tier 2 Deficit |
Tier 1 deficit formula
When it applies: Attained GFI is above the Direct Compliance Target but not above the Base Target.
Tier 1 Deficit = (Attained GFI − Direct Compliance Target) × Energytotal
Tier 1 deficit is expressed as a positive value representing emissions to be remedied.
Tier 2 deficit formula
When it applies: Attained GFI is above the Base Target.
Tier 1 Deficit = (Base Target − Direct Compliance Target) × Energytotal
Tier 2 Deficit = (Attained GFI − Base Target) × Energytotal
Tier 2 Deficit = (Attained GFI − Base Target) × Energytotal
Remedial instruments and pricing
| Instrument | Use case | Current draft design |
|---|---|---|
| Tier 1 Remedial Units | To remedy Tier 1 deficits | Initial price USD 100 per tonne CO₂eq; subject to IMO review mechanism. |
| Surplus Units | Partial remedy or market transfer | May be retained onboard or acquired from other ships; trading rules pending IMO guidance. |
| Tier 2 Remedial Units | To remedy deficits above the Base Target | Initial price USD 380 per tonne CO₂eq. |
| IMO Net-Zero Fund | Receives, manages, and allocates GHG pricing revenue | Supports ZNZ fuel rewards, R&D, infrastructure, capacity building, and a just transition. |
🌱Zero and near-zero fuels and technology incentives
ZNZ definition
ZNZ stands for Zero or Near-Zero GHG emission fuels, technologies and energy sources.
| Period | GFI threshold |
|---|---|
| Through December 2034 | ≤ 19.0 gCO₂eq/MJ |
| From 2035 onward | ≤ 14.0 gCO₂eq/MJ |
Incentive highlights
- Ships using ZNZ fuels or technologies may receive financial rewards from the IMO Net-Zero Fund.
- Reward amounts, eligibility, and application procedures await further IMO guidance.
- ZNZ thresholds and eligible technologies are expected to be reviewed periodically.
📅Revised timeline
April 2025 | MEPC 83
IMO Net-Zero Framework draft text approved and forwarded for adoption.
October 2025 | MEPC/ES.2
Formal adoption not completed; session suspended and postponed to 2026.
April–May 2026 | MEPC 84
Mid-term GHG measures discussed further; no final compromise ready for formal adoption.
November–December 2026 | MEPC 85 and MEPC/ES.2 resumed
Political and technical discussions expected to continue; MEPC/ES.2 resumption on 4 December 2026 remains subject to MEPC 85 confirmation.
After formal adoption
Under MARPOL tacit acceptance, entry into force is expected about 16 months after adoption.
📊CII, SEEMP, and ship energy efficiency
CII reduction factors
MEPC 83 completed Phase 1 review of short-term GHG measures and set CII reduction factors through 2030.
CII reduction factor trend
Baseline: 2019 CII reference line
Reading the chart: 2 percentage points tighter every two years from 2023–2026; 2027–2030 extends to 21.5%, showing steadily rising operational carbon intensity requirements.
CII Phase 2 review
Not fully settled- MEPC 84 launched the Phase 2 review of SEEMP and CII, targeted for completion in 2028.
- SEEMP strengthening includes periodic internal review, continual improvement, stronger audit arrangements, and energy efficiency implementation records.
- Cruise ship cgHRS metric not yet agreed; further sessions planned.
- Adverse-weather CII metrics, reference line adjustments, correction factors, and new indicators remain under review.
CII implementation challenges and current direction
| Issue | Current direction |
|---|---|
| Idle, anchorage, port waiting, and short voyages | Use finer DCS data to assess new metrics or correction factors. |
| Extended cruise port stays | Operational-hour-based cgHRS under discussion; not yet agreed. |
| Severe weather, ship-type specifics, auxiliary loads | Phase 2 review topics requiring more data and proposals. |
| Possible overlap between CII and the Net-Zero Framework | Assess alignment once mid-term GHG measure design is final. |
🗃️DCS, SEEMP, and data transparency
IMO DCS data access
- ROs acting on behalf of flag States may access full data for verification and administration.
- MARPOL Annex VI Parties may access all ship data for analysis.
- Public users may access anonymised data without identifying individual ships.
Aims to improve fuel consumption transparency, support policy analysis, and strengthen assessment of GHG reduction measures.
Underway vs. not-underway data
- From the 2027 reporting year, data will be split into “underway” and “not underway”.
- MEPC 84 clarified: even with split DCS data, CII is still calculated from calendar-year total emissions and distance.
- Voyage distance should also be split underway / not underway to support analysis.
- From the 2027 reporting year, biofuel blend carbon factors will use mass-weighted averaging instead of energy-weighted averaging.
🔬LCA, sustainability standards, and the fifth IMO GHG study
Lifecycle assessment and fuel certification
- LCA guidelines continue expanding fuel pathways, default emission factors, and actual emission factor verification.
- Fuel Lifecycle Label (FLL) will carry fuel origin, emission intensity, and sustainability information.
- GESAMP-LCA continues reviewing default emission factors and harmonising fuel pathway classification.
- Sustainability criteria cover land, water, local development, labour and human rights, and food security.
Fifth IMO GHG study
- Terms of reference finalised at MEPC 84.
- Will support the 2028 IMO GHG strategy review.
- Scope includes international shipping emissions, carbon intensity, future scenarios, and lifecycle emissions analysis.
- Expected to start later in 2026 and complete in 2028.
Default emission factor submission process
| Step | Content |
|---|---|
| 1. Proposal | Submit fuel pathway and emission factor data using the IMO template. |
| 2. Scientific review | GESAMP-LCA reviews by fuel type, data quality, and methodological consistency. |
| 3. Recommended values | Reviewed default emission factor recommendations issued. |
| 4. Inclusion in guidelines | MEPC decides whether to include values in LCA guidelines. |
♻️Other environmental and technical topics
OCCS — onboard carbon capture and storage
- MEPC agreed a work plan for an OCCS regulatory framework.
- Near-term priorities: preventing CO₂ release to sea and air, carbon source tracking, reception facilities, and record-keeping.
- How captured onboard CO₂ counts in emissions accounting remains a dedicated follow-up topic.
- Work plan targets progress by 2028.
CH₄ / N₂O measurement and monitoring
- MEPC 84 adopted technical guidance on methane and nitrous oxide measurement.
- Covers test-bed and onboard measurement, engine load monitoring, and establishing actual Tank-to-Wake emission values.
- Provides technical basis for LCA and future GFI actual emission factors.
NOx Technical Code and engine operating modes
- MEPC 84 completed and approved draft amendments to the NOx Technical Code and related MARPOL amendments.
- Focus areas: multiple engine operating modes, certification of non-carbon and dual-fuel engines, and test cycle clarification.
- Multiple operating mode requirements will affect new engine families and engine groups certified from 1 January 2028.
Ship recycling and biofouling
- Hong Kong Convention enters operational experience building; safe and environmentally sound recycling continues.
- Biofouling management is moving toward a legally binding framework to reduce invasive species transfer.
- IHM guidance updated under MEPC.405(83).
✅Briefing cheat sheet
Must-know points
- MEPC 83: approved the IMO Net-Zero Framework draft — not the same as formal adoption.
- MEPC/ES.2: no adoption in October 2025; postponed to 2026.
- Entry into force: expected ~16 months after formal adoption.
- GFI unit: gCO₂eq/MJ, Well-to-Wake methodology.
- GFI baseline: GFI2008 = 93.3 gCO₂eq/MJ.
Common confusions
- “Draft approved” is not the same as “amendment adopted”.
- Above 5,000 GT refers to ocean-going / international voyaging ships.
- Deficit formulas should express the remedial amount as a positive value.
- CII Phase 2 is underway, but cgHRS and some new metrics are not yet settled.
- Final Net-Zero Framework design may still change through 2026 negotiations.
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