The Back-to-Back LC Failed at the Point Nobody Checked.
Quote from chief_editor on April 12, 2026, 5:24 amBack-to-back LCs in commodity trade create linked obligations. When the timing or terms misalign, the intermediary trader absorbs the gap.
A trading company in Singapore operated as an intermediary between an Indonesian coal supplier and a Vietnamese power utility. The purchase was FOB Samarinda, $62 per MT, 55,000 MT. The sale was CFR Hai Phong, $71 per MT. The gross margin was $9 per MT — roughly $495,000 on the trade. The buyer issued an LC in favor of the trader. The trader opened a back-to-back LC in favor of the supplier, using the buyer's LC as the underlying security.
The buyer's LC required presentation of documents within 21 days of the BL date, with an expiry date of May 15. The trader's LC to the supplier had a presentation window of 15 days from BL date, expiry May 10 — five days earlier than the buyer's LC to give the trader time to receive the supplier's documents, substitute invoices, and present to the buyer's bank. The vessel loaded on April 18. The supplier's documents arrived at the trader's bank on April 30. The trader received them on May 2. The trader had until May 9 — the business day before the buyer's LC expiry — to present to the buyer's bank. The trader had 7 calendar days to check documents, substitute, and present.
On May 3, the trader discovered that the quality certificate referenced the wrong LC number. The surveyor needed 3 days to reissue. The corrected certificate arrived on May 6. The trader presented to the buyer's bank on May 7. The bank found a second discrepancy — the BL showed the consignee as the trader's bank rather than the buyer's bank, because the trader's back-to-back LC had different banking details. The trader could not correct this discrepancy because the BL had been issued at the load port weeks earlier. The presentation was refused. The buyer's LC expired without payment.
The trader had paid the supplier under the back-to-back LC — that LC had processed cleanly because the documents conformed to the supplier's LC terms. The trader had spent $3.41 million. The trader had not been paid by the buyer. The cargo was at Hai Phong. The buyer eventually paid, but only after a 47-day negotiation during which the buyer extracted a $3 per MT discount, reducing the trader's margin from $495,000 to $330,000. The demurrage during the negotiation period — $16,500 per day for 12 days of vessel delay — added $198,000 in costs. The trader's net result on the trade was approximately $132,000, down from the original $495,000.
The Two LCs Serve Different Parties and Must Be Mirrored Precisely
Back-to-back LCs create a chain where the trader's payment to the supplier depends on the supplier's document compliance, and the trader's receipt of payment from the buyer depends on the trader's ability to re-present documents that comply with the buyer's LC terms. These are two separate compliance tests. The documents that satisfy the supplier's LC are not automatically compliant with the buyer's LC. The consignee, the notify party, the bank details, the description of goods, the document format requirements — all of these can differ between the two LCs.
The risk sits in the gap between the two LCs: differences in terms that require document substitution, and the time available to perform that substitution. If the trader has 7 days between receiving documents from the supplier and the buyer's LC expiry, every day consumed by discrepancy correction, courier delays, or bank processing time reduces the margin for error.
The critical operational discipline for back-to-back LC trades is term mirroring: the trader must ensure that every documentable requirement in the buyer's LC is either identical to the corresponding requirement in the supplier's LC, or can be satisfied by document substitution within the available time window. This means comparing the two LCs clause by clause before the supplier's LC is opened — not after the cargo has loaded.
Specific points that frequently cause misalignment include: consignee and notify party in the BL (the supplier's LC names the trader's bank; the buyer's LC names the buyer's bank), description of goods (the supplier's LC may use technical specifications; the buyer's LC may use a commercial description), presentation period (if the supplier's LC allows 21 days but the buyer's LC allows only 14, the trader has negative time for substitution), and document originals (some LCs require three original BLs, others require a full set — the number matters when substitution requires forwarding originals).
The Time Window Is the Trader's Real Constraint
The financial risk of back-to-back LCs is concentrated in the time gap between receiving documents from the supply side and presenting to the buy side. The trader who structured this coal trade allowed a 5-day gap between the two LC expiry dates. That gap assumed no document discrepancies, no courier delays, and no need for corrections. When a single discrepancy consumed 3 of those 5 days, and a second discrepancy could not be corrected at all, the entire margin structure of the trade collapsed.
Traders who handle back-to-back LCs routinely build a minimum 10-business-day gap between the supply LC expiry and the buy LC expiry, specifically to accommodate at least one round of document correction. They specify that the supplier's LC must use document terms that are identical to or more restrictive than the buyer's LC requirements, so that any document complying with the supplier's LC automatically complies with the buyer's LC. And they insist on electronic document transmission where possible — scanned copies for pre-checking before originals are couriered — to identify discrepancies while there is still time to correct them.
The $363,000 this trader lost — the difference between the expected margin and the actual result — was not caused by market movement, credit default, or cargo quality failure. It was caused by a 5-day time window that was too short to absorb two document discrepancies. The structure of the trade assumed that documents would be perfect. Documents in physical commodity trade are rarely perfect. The traders who build their LC structures on the assumption of perfection are the ones who discover, trade by trade, that the margin they calculated was theoretical and the margin they earned was whatever was left after the document process consumed its share.
Keywords: back to back LC risk physical commodity trade failure | back to back letter of credit commodity, intermediary trader LC gap risk, LC term mismatch commodity trade, transferable LC vs back to back risk
Words: 1031 | Source: Industry pattern — documented across multiple sources | Created: 2026-04-08
Back-to-back LCs in commodity trade create linked obligations. When the timing or terms misalign, the intermediary trader absorbs the gap.
A trading company in Singapore operated as an intermediary between an Indonesian coal supplier and a Vietnamese power utility. The purchase was FOB Samarinda, $62 per MT, 55,000 MT. The sale was CFR Hai Phong, $71 per MT. The gross margin was $9 per MT — roughly $495,000 on the trade. The buyer issued an LC in favor of the trader. The trader opened a back-to-back LC in favor of the supplier, using the buyer's LC as the underlying security.
The buyer's LC required presentation of documents within 21 days of the BL date, with an expiry date of May 15. The trader's LC to the supplier had a presentation window of 15 days from BL date, expiry May 10 — five days earlier than the buyer's LC to give the trader time to receive the supplier's documents, substitute invoices, and present to the buyer's bank. The vessel loaded on April 18. The supplier's documents arrived at the trader's bank on April 30. The trader received them on May 2. The trader had until May 9 — the business day before the buyer's LC expiry — to present to the buyer's bank. The trader had 7 calendar days to check documents, substitute, and present.
On May 3, the trader discovered that the quality certificate referenced the wrong LC number. The surveyor needed 3 days to reissue. The corrected certificate arrived on May 6. The trader presented to the buyer's bank on May 7. The bank found a second discrepancy — the BL showed the consignee as the trader's bank rather than the buyer's bank, because the trader's back-to-back LC had different banking details. The trader could not correct this discrepancy because the BL had been issued at the load port weeks earlier. The presentation was refused. The buyer's LC expired without payment.
The trader had paid the supplier under the back-to-back LC — that LC had processed cleanly because the documents conformed to the supplier's LC terms. The trader had spent $3.41 million. The trader had not been paid by the buyer. The cargo was at Hai Phong. The buyer eventually paid, but only after a 47-day negotiation during which the buyer extracted a $3 per MT discount, reducing the trader's margin from $495,000 to $330,000. The demurrage during the negotiation period — $16,500 per day for 12 days of vessel delay — added $198,000 in costs. The trader's net result on the trade was approximately $132,000, down from the original $495,000.
The Two LCs Serve Different Parties and Must Be Mirrored Precisely
Back-to-back LCs create a chain where the trader's payment to the supplier depends on the supplier's document compliance, and the trader's receipt of payment from the buyer depends on the trader's ability to re-present documents that comply with the buyer's LC terms. These are two separate compliance tests. The documents that satisfy the supplier's LC are not automatically compliant with the buyer's LC. The consignee, the notify party, the bank details, the description of goods, the document format requirements — all of these can differ between the two LCs.
The risk sits in the gap between the two LCs: differences in terms that require document substitution, and the time available to perform that substitution. If the trader has 7 days between receiving documents from the supplier and the buyer's LC expiry, every day consumed by discrepancy correction, courier delays, or bank processing time reduces the margin for error.
The critical operational discipline for back-to-back LC trades is term mirroring: the trader must ensure that every documentable requirement in the buyer's LC is either identical to the corresponding requirement in the supplier's LC, or can be satisfied by document substitution within the available time window. This means comparing the two LCs clause by clause before the supplier's LC is opened — not after the cargo has loaded.
Specific points that frequently cause misalignment include: consignee and notify party in the BL (the supplier's LC names the trader's bank; the buyer's LC names the buyer's bank), description of goods (the supplier's LC may use technical specifications; the buyer's LC may use a commercial description), presentation period (if the supplier's LC allows 21 days but the buyer's LC allows only 14, the trader has negative time for substitution), and document originals (some LCs require three original BLs, others require a full set — the number matters when substitution requires forwarding originals).
The Time Window Is the Trader's Real Constraint
The financial risk of back-to-back LCs is concentrated in the time gap between receiving documents from the supply side and presenting to the buy side. The trader who structured this coal trade allowed a 5-day gap between the two LC expiry dates. That gap assumed no document discrepancies, no courier delays, and no need for corrections. When a single discrepancy consumed 3 of those 5 days, and a second discrepancy could not be corrected at all, the entire margin structure of the trade collapsed.
Traders who handle back-to-back LCs routinely build a minimum 10-business-day gap between the supply LC expiry and the buy LC expiry, specifically to accommodate at least one round of document correction. They specify that the supplier's LC must use document terms that are identical to or more restrictive than the buyer's LC requirements, so that any document complying with the supplier's LC automatically complies with the buyer's LC. And they insist on electronic document transmission where possible — scanned copies for pre-checking before originals are couriered — to identify discrepancies while there is still time to correct them.
The $363,000 this trader lost — the difference between the expected margin and the actual result — was not caused by market movement, credit default, or cargo quality failure. It was caused by a 5-day time window that was too short to absorb two document discrepancies. The structure of the trade assumed that documents would be perfect. Documents in physical commodity trade are rarely perfect. The traders who build their LC structures on the assumption of perfection are the ones who discover, trade by trade, that the margin they calculated was theoretical and the margin they earned was whatever was left after the document process consumed its share.
Keywords: back to back LC risk physical commodity trade failure | back to back letter of credit commodity, intermediary trader LC gap risk, LC term mismatch commodity trade, transferable LC vs back to back risk
Words: 1031 | Source: Industry pattern — documented across multiple sources | Created: 2026-04-08