· Gökçen Özkan
The Paper That Leaves the Barge: The BDN's Second Life in Türkiye
Every master and chief engineer who has bunkered knows the moment. The barge is alongside, the hose is connected, the surveyor is gauging tanks and it is past midnight. Then a few copies of paper arrive in front of you. Quantity, density, sulphur, flashpoint, and a line for your signature. If a dispute follows, that paper, any remark you wrote on it and a letter of protest are all you have.
That paper is the Bunker Delivery Note, the BDN. MARPOL Annex VI Regulation 18.5 requires it and Regulation 18.6 requires it to be kept on board for at least three years. It is one of the first documents a port state control officer asks for.
IMO opened the door in 2023
For years "retained on board" was read as a paper copy. In July 2023, MEPC 80 changed that. Its unified interpretation (MEPC.1/Circ.795/Rev.8) says a BDN may be electronic, on four conditions: it contains the Appendix V information, it is retained per Regulation 18.6, it is protected from later edits, and it can be authenticated by a method such as a tracking number, watermark, time stamp, QR code or GPS.
One point matters here. IMO does not require a qualified electronic signature; a QR code may meet the minimum. Internationally, the benefit of a strong signature is evidential weight, not legal necessity. I say this plainly because overstatements such as "IMO mandates cryptographic locking" circulate in the industry and lose a careful reader in the first line.
Singapore turned permission into a system
The Maritime and Port Authority of Singapore went through that door first. It started voluntarily in November 2023 and made e-BDNs the default from 1 April 2025. The structure it built matters more than the date:
Suppliers may only use solutions on MPA's whitelist; six providers are listed today.
Banks and shipowners can check an e-BDN they receive against the record transmitted to MPA.
Document data is defined by the SS 709:2024 standard, and the mass flow metering code SS 648 was revised to add data integrity requirements.
Singapore did not simply turn paper into PDFs. It built an arrangement in which a third party can confirm who issued a document, when, and that it has not changed.
Europe is taking a different route. Since 1 January 2026, Rotterdam and Antwerp-Bruges require certified mass flow meters on bunker vessels. e-BDNs are still at trial stage there. Measurement first, documents second.
In Türkiye the BDN has a second life
The industry knows the story so far. What is often missed about Türkiye is that here the BDN is not only a MARPOL document. It is also a customs record.
Under the Ministry of Trade's Circular 2024/3 on bunker deliveries ("ihrakiye"), barge deliveries are, as a rule, escorted by a customs officer. Unescorted delivery needs all of the following: a fixed guarantee of USD 2 million (75% for Authorised Economic Operators); every stage supervised by an expert from a Type (A) international surveillance company; a barge camera system recording 24 hours with footage kept for 30 days; AIS on at all times. Most important of all, by the end of the next working day the BDNs for barge loading and for delivery to the ship, the surveyor's seal records, time log, tank ullage report, sample receipt and the broken customs seals are handed to customs.
One delivery produces at least two BDNs, five surveyor documents, two seal records and a video record. Most of it is produced on paper, by different hands, at different times. There is an irony too: the circular itself is signed with a secure electronic signature and carries a QR code. The state writes the rule electronically; the chain the rule governs still runs on paper.
Türkiye's equivalent of Singapore's engine
In Singapore the port authority carried e-BDN adoption. In Türkiye, an authority with a direct fiscal interest in the BDN's accuracy already exists: customs. Bunkers delivered as "ihrakiye" are treated as exports. The more trustworthy the document chain, the less of the control burden has to sit on guarantees and escorts.
So in my view the e-BDN conversation in Türkiye should start not with "owners will demand it for ESG", but with the customs submission that already exists. The question is this: can the paper file carried to customs the next day become an electronic file that is sealed, time-stamped and verifiable at the moment each record is created?
What a signature solves and what it does not
Honesty is needed here. Most bunker disputes are about quantity and quality, not forged signatures. An electronic signature does not prove how many tonnes were delivered or what was in them. Quantity comes from measurement, quality from the sample.
The signature does something else. It proves who produced the surveyor's gauging, the time log, the seal numbers and the BDN, at what time, and that none of it changed afterwards. Under Turkish law a secure electronic signature has the same legal effect as a handwritten one (Law No. 5070, Article 5). Together with a legal-entity e-seal and a time stamp, it gives an indisputable answer to "who recorded what, on that day, at that time".
Where we start
At Maresign we are opening this as a working area. We do not sell an e-BDN product today, and we do not produce the trust infrastructure: qualified e-signatures, e-seals, time stamps and identity verification come from our solution partner ArkSigner, a BTK-authorised qualified electronic certificate service provider (NESHS). Our job is to fit that infrastructure to maritime workflows.
The first step is listening to the field. We want to talk to EPDK-licensed bunker companies, Type (A) surveillance companies, bunker surveyors and customs brokers. What is hard about next-day submission? How often do disputes arise? Where are camera and seal records kept, and for how long?
If you are a link in this chain, write to me: gokcen.ozkan@maresign.com
Our page with the full sources: maresign.com/insights/e-bdn
This article is for information and is not legal advice.
Sources
IMO, MEPC.1/Circ.795/Rev.8 — Unified Interpretations to MARPOL Annex VI
MPA Singapore, Digital Bunkering — mpa.gov.sg
Ministry of Trade of Türkiye, Circular 2024/3 on Bunker Deliveries, Annexes 2 and 4
Port of Rotterdam, Bunkering in Rotterdam
Turkish Electronic Signature Law No. 5070, Art. 5