· Gökçen Özkan
e-BDN in Türkiye: What IMO Says, What Singapore Did, and the Customs Chain
Short answer
e-BDNs are valid under international rules but not yet defined in Türkiye. IMO accepted electronic BDNs in 2023. Singapore made them the default in 2025 and built a central verification record. We have found no Turkish rule specific to e-BDNs. However, under Customs Circular 2024/3 the BDN already sits inside a document chain of customs seals, surveyor records and camera footage. That chain is the natural place to start digitalising.
What is an e-BDN?
The BDN is the document a fuel supplier gives the receiving ship at every delivery, as required by MARPOL Annex VI Regulation 18.5. It must be kept on board for at least three years and be available for inspection (Regulation 18.6). An e-BDN is the same document in electronic form. The content stays the same; the medium changes.
Minimum content under Appendix V:
Field | Content |
|---|---|
Ship | Name and IMO number of the receiving ship |
Place / time | Port; date of commencement of delivery |
Supplier | Name, address and telephone number |
Product | Product name; quantity in metric tonnes; density at 15°C (kg/m³) |
Sulphur | Sulphur content (% m/m) |
Flashpoint | Measured value (°C) or a statement that it was measured at or above 70°C (since 1 May 2024) |
Declaration | Declaration signed and certified by the supplier's representative |
Since 1 January 2026, the SOLAS II-2/4.2.1 amendments also require the supplier to give the ship, before bunkering, a signed and certified declaration that the fuel's flashpoint is compliant. This may be included in the BDN.
What does IMO say?
Electronic BDNs are acceptable, subject to four conditions. In July 2023, MEPC 80 agreed a unified interpretation of MARPOL Annex VI Regulations 18.5 and 18.6, now in circular MEPC.1/Circ.795/Rev.8.
A BDN may be in hard copy or electronic format. An electronic BDN should:
contain at least the Appendix V information,
be retained and available on board in line with Regulation 18.6,
be protected from edits, modifications or revisions,
allow authentication by a verification method such as a tracking number, watermark, date and time stamp, QR code, GPS coordinates or other methods.
The interpretation sets a minimum and uses "should" language. It does not require a cryptographic or qualified electronic signature; a QR code may satisfy it. Internationally, the value of a qualified signature is therefore evidential strength, not legal necessity.
What did Singapore do?
It turned permission into a default, and the default into a verifiable system. The Maritime and Port Authority of Singapore (MPA) launched voluntary e-BDNs on 1 November 2023. Since 1 April 2025, bunker suppliers issue e-BDNs by default.
Three parts of the model
Whitelist. Suppliers and bunker craft operators must use digital bunkering solutions whitelisted by MPA for conformance to bunkering standards, cybersecurity, baseline functionality, risk management and regulatory reporting. As of September 2026 there are six: Angsana (BunkerFlow), ZeroNorth (digitalBunkering@Sea), Bunkerchain (Touch and Sail), TradeGo (BunkerGo), Ofiniti (Fuelboss) and Brightree (BrightNote).
Central verification. Banks and shipowners can check e-BDN data they receive against the record transmitted to MPA, through the digitalPORT@SG portal.
Standard. SS 709:2024, published in November 2024, specifies digital bunkering supply chain documents and how they are issued. The mass flow metering code SS 648 was revised to add data integrity and transmission requirements.
MPA defines digital bunkering as workflow, electronic signing and stamping of documents, authentication, access control and verifiable records together. It expects the industry to save close to 40,000 man-days a year.
Europe
Since 1 January 2026, Rotterdam and Antwerp-Bruges require certified mass flow meters (MFM) on bunker vessels delivering fuel oil, distillates and biofuels. e-BDNs are not mandatory in the ARA region and are at trial stage; the first trial took place in Rotterdam in October 2025.
How does Türkiye's bunkering chain work?
In Türkiye the BDN already works as a customs document. Circular 2024/3 on bunker deliveries ("ihrakiye") of the Ministry of Trade, Directorate General of Customs, rests on Article 176 of Customs Law No. 4458 and Articles 476–482 of the Customs Regulation. Barge deliveries are, as a rule, escorted by a customs officer. Unescorted delivery requires all of the following.
EPDK (Energy Market Regulatory Authority) licences for the delivering and carrying companies,
a fixed guarantee of USD 2,000,000 (75% of that for Authorised Economic Operators),
every stage supervised by an expert from a company holding Type (A) international surveillance status from the Ministry,
a barge camera system recording at 1080p, at least 15 fps, day and night, 24 hours, with footage kept for at least 30 days; AIS on at all times,
submission to customs, by the end of the next working day, of the surveyor's records, the BDNs for loading the barge and for delivery to the ship, and the broken customs seals.
The document chain, step by step
Step | What happens | Records |
|---|---|---|
1. Barge loading | Fuel is loaded from the bonded store; barge tanks are sealed by customs. | BDN (barge loading), customs seal |
2. Transit and berthing | Barge cameras record continuously and AIS stays on. The surveyor stays on the barge from alongside to departure. | camera footage, AIS track |
3. Seal breaking | The surveyor breaks the seals and records their numbers with the barge officer. | seal-breaking record |
4. Delivery | A time log runs from alongside to completion; tanks are gauged before and after; samples are drawn. | time log, tank ullage report, sample receipt, BDN (delivery to ship) |
5. Re-sealing | Barge tanks are sealed again and the new numbers recorded. | re-sealing record, new seals |
6. Submission to customs | By close of business on the next working day, all records, the BDNs and the broken seals go to the customs office. | all records, BDN × 2, broken seals |
The chain holds at least two BDNs, five surveyor documents, two seal records and a video record. Most are still produced on paper, by different hands, at different times. The circular itself is signed with a secure electronic signature and carries a QR code. The state issues the rule electronically; the chain it governs still runs on paper.
Why it matters for Türkiye
In Singapore the port authority drove e-BDN adoption. In Türkiye, an authority with a direct fiscal interest in the BDN already exists: customs. Bunkers delivered as "ihrakiye" are treated as exports, and the tax treatment depends on it. The more trustworthy the document chain, the less control has to rest on guarantees and escorts.
The second push is commercial. Ships under the EU's FuelEU Maritime regulation must give their verifier the BDN and, for biofuels, proof of sustainability. That does not make e-BDNs a legal requirement. But for an owner bunkering in Türkiye and trading to EU ports, a reliable, machine-readable BDN is directly useful in compliance reporting.
What an electronic signature does and does not solve
This needs saying up front. Most bunker disputes come from quantity and quality differences, not forged signatures.
Solves
Who issued and approved the document (legal-entity e-seal, personal e-signature)
When it was issued (time stamp)
Whether it changed afterwards (integrity)
Whether the approver is really that person (identity verification)
Under Turkish law, a secure electronic signature has the same legal effect as a handwritten one (Law No. 5070, Art. 5)
Does not solve
The actual quantity delivered (that comes from MFM, tank gauging, surveyors)
Fuel quality (that comes from the MARPOL sample and lab analysis)
Meter calibration
Wrong data entered in the first place
The signature's real job is to seal measurement and survey data the moment it is created, so it cannot be changed later. In a dispute, that answers "who recorded what, on that day, at that time" beyond argument.
What Maresign is doing
This is a working area, not a product on sale. Maresign does not yet offer a commercial e-BDN solution. Our aim is to design a pilot with the field for digitalising the bunkering document chain in line with Turkish law and customs practice.
Maresign does not produce the trust infrastructure. Qualified e-signatures, e-seals, time stamps and identity verification come from ArkSigner, a qualified electronic certificate service provider (NESHS) authorised by Türkiye's ICTA (BTK). Maresign, as ArkSigner's contracted solution partner and reseller, integrates that infrastructure and builds the application layer for maritime workflows.
Who we want to talk to
EPDK-licensed bunker delivery companies and barge operators,
Type (A) international surveillance companies and bunker surveyors,
customs brokers,
technical and compliance teams of owners and operators who bunker regularly in Türkiye.
The first step is a 30–45 minute conversation: what is hard about next-day submission, how often disputes arise, and where camera and seal records are kept.
gokcen.ozkan@maresign.com
Frequently asked questions
What is an e-BDN?
The electronic form of the Bunker Delivery Note. Under MARPOL Annex VI Regulation 18.5, the supplier gives the ship a BDN at each delivery. It contains the Appendix V minimum information and is kept on board for at least three years under Regulation 18.6.
Does IMO accept electronic BDNs?
Yes. The MEPC 80 unified interpretation (MEPC.1/Circ.795/Rev.8) accepts hard copy or electronic format, provided the BDN contains the Appendix V information, is retained per Regulation 18.6, is protected from edits, and can be authenticated by a method such as a tracking number, watermark, time stamp, QR code or GPS. No qualified signature is required.
How did Singapore make e-BDNs mandatory?
MPA started voluntary e-BDNs on 1 November 2023. From 1 April 2025 suppliers issue them by default, using only MPA-whitelisted solutions. Banks and owners can verify records through digitalPORT@SG. The data format is set by SS 709:2024.
Are e-BDNs mandatory in Türkiye?
As far as we can determine, no. But under Customs Circular 2024/3, for unescorted barge deliveries the BDN is submitted to customs by the next working day together with surveyor records and broken customs seals.
What does an e-signature or e-seal solve on a BDN?
It proves who issued the document, when, and that it has not changed. It does not prove the quantity or quality of the fuel; those come from metering, surveying and sample analysis. The signature's job is to seal that data at the moment it is created.
What is Maresign doing on e-BDNs?
Maresign treats this as a working area and does not yet offer a commercial product. The trust infrastructure comes from ArkSigner, a BTK-authorised NESHS. Maresign, as solution partner, builds the application layer and is looking for pilot partners among licensed bunker companies, surveyors and customs brokers.
Sources
IMO, MEPC.1/Circ.795/Rev.8, Unified Interpretations to MARPOL Annex VI
Lloyd's Register, Class News 02/2024: electronic Bunker Delivery Notes
MPA Singapore, Digital Bunkering (accessed 28.09.2026)
MPA Singapore, SIBCON 2024 media release
MARPOL Annex VI, Regulations 18.5, 18.6 and Appendix V (IMO)
Lloyd's Register, Class News 06/2024: SOLAS II-2/4.2.1, MSC.520(106) and MSC.550(108)
Port of Rotterdam, Bunkering in Rotterdam; Port of Antwerp-Bruges, Bunkering
Ship & Bunker, Bunker Suite e-BDN trial, Rotterdam
Ministry of Trade of Türkiye, Directorate General of Customs, Circular 2024/3 on Bunker Deliveries, Annexes 2 and 4 (in Turkish)