Before You Transit the Red Sea: A Practical, In‑Depth Guide for Vessels & Companies

What to do today — step‑by‑step due diligence, how to detect links to Israel/UK/US entities, and why “dark port calls” matter.

Transiting the Red Sea and Gulf of Aden in the current threat environment is no longer routine. The Houthis explicitly base targeting on political and commercial linkages (port calls, ownership, charters and corporate affiliations), and they have publicly expanded their targeting criteria across several declared phases. Shipowners, managers and charterers must therefore treat company and vessel provenance as a core safety risk — not just a reputational or compliance issue.

Below is a practical, operational article you can use as a procedure or checklist. It covers: (A) pre‑transit intelligence and affiliation checks, (B) how to detect and verify “dark port calls”, (C) what to do if you find linkages to Israel / UK / US entities, and (D) immediate shipboard and commercial mitigations.

1) Pre‑transit intelligence & corporate affiliation check — step by step

Goal: generate an auditable risk profile that shows whether a vessel, its owner/operator/manager/charterer, or its corporate group has direct or indirect links to Israel, the UK, or the US — any of which can increase Houthi targeting risk.

1. Assemble identifiers (minimum):

   • IMO number, vessel name(s) (and previous names), call sign, MMSI, flag, gross tonnage.

   • Company identifiers: registered owner, beneficial owner(s), technical manager, commercial manager, operator/ship manager, charterer (time/voyage), and registered address(es).

2. Ship registry & ownership chain:

   • Query primary public registries (flag state registry) and open registers to identify the registered owner and ship manager.

   • Trace the ownership chain up to the ultimate beneficial owner (UBO). Look for parent companies, holding companies, and known corporate umbrellas headquartered or registered in Israel, the UK, or the US.

   • Record company registration numbers and dates; screenshot or save registry pages for audit.

3. Corporate and commercial link checks:

   • Search for the operator/manager and charterer corporate websites and corporate filings for evidence of business ties, joint ventures, or subsidiaries with Israeli, UK or US entities.

   • Check recent charterparty records or fixture reports (if available) for Israeli ports, Israeli companies, or Israeli intermediaries named in past voyages.

4. Sanctions and watchlist screening:

   • Screen owners, managers, charterers, and beneficial owners against sanctions/watchlists (OFAC/US Treasury, UK HMT, EU, Israeli lists). Even a denied‑party or sanctioned intermediary in the corporate chain is a red flag.

   • Screen key senior executives by name where possible.

5. AIS & voyage history audit (summary; see section 2 for dark calls):

   • Pull the vessel’s AIS voyage history for the past 6–12 months and map port calls, ETA/ETD patterns and any unexplained AIS gaps.

   • Identify any port calls to Israeli ports (e.g., Ashdod, Haifa, Ashkelon, etc.) and the dates.

6. Commercial‑intelligence validation:

   • Where possible, obtain an independent commercial intelligence check from a maritime intelligence provider (subscription) or use OSINT techniques: shipping press, port agent notices, bunker delivery receipts (BDRs), port clearance data and port authority entries.

7. Record & score risk:

   • Create a simple risk scorecard: direct Israeli port calls = high, indirect via same corporate group = high‑medium, UK/US ownership = medium (phase‑dependent), previous attacks/near‑miss = very high.

   • Document supporting evidence and date‑stamp it.

     
     

2) Dark port calls — what they are and how to detect them

Definition: A dark port call is a port visit or berth activity that is not visible via normal public AIS records or transparent port reporting — often because AIS was switched off, spoofed, or manipulated, or because the ship used an intermediary identity (renamed, false flag) while in port. Dark calls can also appear as suspicious AIS gaps that align with known port geographies or as inconsistencies between port agency records and published AIS logs.

Why they matter: The Houthis and similar actors use open‑source and commercial maritime intelligence to link ships to targeted countries. A vessel that “goes dark” before or during a port call may indicate deliberate concealment of visits to sensitive ports — and that concealment, if discovered, can be interpreted as evidence of an Israel link.

Detection techniques:

• AIS gap analysis: correlate the ship’s AIS track with known port coordinates. A sudden loss of AIS signal within port approach corridors — combined with a prolonged static position — is a red flag.

• Satellite AIS & multi‑source AIS: compare terrestrial AIS with satellite AIS feeds. Satellite AIS often fills in gaps when terrestrial reception fails; if satellite AIS shows a port visit but terrestrial AIS does not, this indicates deliberate AIS switching.

• LRIT & voyage data (where accessible): LRIT (Long Range Identification and Tracking) records and voyage data reported to flag/port authorities can corroborate or contradict AIS.

• Port agent & port authority records: request port call confirmations, berthing invoices, pilotage receipts, cargo operations receipts, and bunker delivery notes from the port agent — these records will show a physical port call even when AIS is dark.

• Bunker delivery receipts & bills of lading: BDRs and B/Ls often reveal the last physical port and date. Cross‑check these against AIS.

• Open‑source intelligence: satellite imagery (berth imagery), port community posts, local shipping news, and social media may provide independent confirmation.

• Historical name/flag matching: ships that changed name/flag shortly before or after suspicious AIS gaps often indicate attempts to obfuscate a port call.

Red flags to capture:

• AIS turned off for >4 hours in a port approach or berthing zone.

• Discrepancy between AIS and satellite AIS.

• Rapid name/flag change within 30 days of suspicious movement.

• Port agent unable or unwilling to provide standard arrival/departure paperwork.

  
  

3) If you find links to Israel / UK / US — what to do

1. Risk reassessment: escalate to senior ops, safety and legal teams; reclassify the transit as high‑risk if you have direct or corporate links.

2. Notify insurers & P&I club immediately: seek guidance about cover implications and record their recommendations.

3. Inform charterers / commercial partners: request clarifying declarations — e.g., a signed statement that the ship has not called Israeli ports in the last X months (template below).

4. Consider rerouting or delay: where commercial timelines allow, delay or reroute via the Cape of Good Hope.

5. Decide on escorts / armed protection: consult legal counsel about the legality of private armed guards in your flag state; coordinate with naval task forces for escorts and clear ROE constraints.

6. Enhance on‑board posture: heightened watch, citadel drills, firefighting readiness and medical evacuation plans.

4) Immediate operational & procedural mitigations prior to transit

• File voyage plan with UKMTO / MSCIO/ Flag state / Coastal authorities and maintain regular reporting cadence.

• Maintain continuous AIS where safely possible; avoid “going dark” unless ordered by competent authority. If AIS is turned off for safety, document the reason and notify authorities.

• Citadel & fire readiness: train crew on citadel, anti‑boarding, firefighting for missile/rocket impacts and evacuation/RIB deployment.

• Medical & evacuation: prearrange medevac and diversion ports (e.g., Djibouti, Aden alternatives).

• Communications: establish direct contact lines with company security officer, naval point-of-contact, and designated port agents.

• Insurance & contractual clauses: ensure war risk cover is valid and P&I clubs are notified of the transit.

  
  

5) Governance, documentation & audit trail

• Maintain a persistent audit pack for each transit: affiliation checks, AIS records, satellite AIS screenshots, port documents, owner/manager declarations, insurance notifications and risk scorecard.

• Keep decisions and authorisations signed off by shipmaster, CSO/security manager and nominated commercial/charter authority.

  
  

Final note — legal & reputational cautions

Treat all findings as operational intelligence subject to verification. False positives (e.g., mistaken port identification) can occur, and in some jurisdictions requesting certain documentation may trigger privacy or commercial pushback. Always coordinate with legal counsel and P&I clubs before taking exclusionary commercial action.