Methodology & Data Sources

How ArcNautical scores a vessel

Every verdict on this site is computed from named, citable sources with disclosed thresholds. No black box: the sources, the exact cut-offs, the weights, and what we will not claim are all on this page.

Every figure carries an “as of” date · the live /check tool re-screens in real time

Data sources

ArcNautical does not publish its own sanctions designations or detention records. It screens against, and cites, the authoritative public sources below — each lookup carries the source name and the date it was read.

SourceUsed forRefresh
OFAC SDN List
U.S. Treasury, Office of Foreign Assets Control
Sanctions screeningDaily · search
EU Consolidated Financial SanctionsSanctions screeningDaily · map
UN Security Council Consolidated ListSanctions screeningDaily · list
UK HMT / OFSI Consolidated ListSanctions screeningDaily
OpenSanctionsConsolidated + vessel datasetsDaily · site
GLEIF Global LEI IndexOwnership chain & beneficial owner24h cache · search
Paris MoUFlag-state PSC performance (White/Grey/Black)Annual list, WGB 2021–2023 · site
Tokyo MoUFlag-state PSC performanceAnnual list, 2023 · site
EquasisPSC inspection & detention historyPer lookup · site
AISPosition & port-call historyContinuous

Paris and Tokyo MoU White/Grey/Black placements were last reconciled against the published annual lists on 2026-05-30.

The sanctions verdict — RED / AMBER / GREEN

The headline status answers one question: does this hull match a current sanctions listing?

RED
Confirmed match. The vessel's IMO or MMSI exactly matches a sanctions-list entry, or another high-confidence identifier match is present. The matched list and entry are shown.
AMBER
Potential match — low confidence. At least one name or fuzzy match exists that is not identity-confirmed. AMBER is a prompt to verify, never a conclusion.
GREEN
No matches across OFAC SDN, EU, UN, UK HMT/OFSI, and OpenSanctions vessel lists at the time of screening.

Match confidence is ranked exact IMO → exact MMSI → name + flag → fuzzy name. Only an exact identifier (or otherwise high-confidence) match produces RED; everything weaker is AMBER and flagged for human review.

Ownership opacity — 0 to 100

Opacity measures how hard it is to see who actually controls a vessel. 0 is fully transparent; 100 is opaque. The score is driven by how far the corporate chain resolves in the GLEIF LEI index, whether the registered owner sits in a shell-company jurisdiction, and whether a beneficial owner is disclosed.

LOW
0–30. Registered entity and parent chain resolvable in GLEIF.
MEDIUM
31–60. Partial resolution — some chain or owner detail missing.
HIGH
61–100. No GLEIF record and/or registration in a shell-company jurisdiction with no beneficial-owner disclosure.

Shell-company jurisdictions weighted toward opacity

MH · PA · LR · VG · KY · BM · GI · IM · JE · GG · BS · SC · MU · CW · AG · WS · VU · KM · TO

The vetting grade — A to E

The vetting grade is a single weighted composite (0–100, where lower is better) mapped to a letter. It blends five independent risk signals:

30%
Detention history (PSC)
25%
Flag-state performance
20%
Ownership opacity
15%
Vessel age
10%
Inspection gap
A
0–20
B
21–40
C
41–60
D
61–80
E
81–100
Three things we do deliberately, and disclose:
  • A confirmed sanctions match floors the grade to E, regardless of the underlying feature scores. A sanctioned hull is never graded "moderate".
  • When Port-State-Control data is unavailable, the detention weight is redistributed to the remaining signals — we do not invent a detention score to fill the gap.
  • Only signals backed by real data contribute to the average (active-signal weighting). A missing signal is excluded, not silently scored zero.

Freshness

Sanctions and inspection data change constantly. Every baked figure on a vessel, flag, or entity page carries the snapshot date it was read. For a current answer, the free /check tool re-screens the vessel against the live lists at the moment you query it.

Limitations & responsible use

Who builds this

ArcNautical is built and maintained by Madhav PVLinkedIn. It is independent maritime intelligence, not affiliated with any sanctions authority, flag registry, or classification society. Questions about a specific result or the methodology are welcome at [email protected].