MT700 Field 77b — Contradictions with Other Fields

Introduction

SWIFT MT700 Field 77b contains instructions related to amendments to a documentary credit. When Field 77b contradicts other fields in the same MT700 message, the amendment process becomes ambiguous, potentially leaving parties uncertain about whether the credit has been validly amended and what terms apply.

Failure Modes

1. Field 77b Amends Terms Inconsistent with Field 32B (Amount)
If Field 77b modifies the credit amount without updating Field 32B, the message contains contradictory amount information.

2. Field 77b Contradicts Field 48 (Presentation Period)
If Field 77b extends the credit's validity but does not update Field 48, the presentation period may no longer align with the amended validity period.

3. Field 77b References an Amendment Number That Does Not Match the Credit
If Field 77b references "Amendment 3" but the credit is only on its second amendment, the reference creates confusion about which amendment is being transmitted.

4. Field 77b Contradicts Field 49 (Instructions to Paying Bank)
If Field 77b modifies payment terms but Field 49 retains the original instructions, the two fields conflict on how payment should be processed.

Resolution Steps

1. Cross-reference Field 77b against all fields affected by the amendment before transmitting the MT700. Ensure consistency across Fields 32B, 48, 49, and other impacted fields.

2. Use the amendment number consistently across Field 77b and any related correspondence or documentation.

3. When Field 77b modifies payment terms, update Field 49 accordingly to reflect the new instructions.

4. Verify that Field 77b content is consistent with Article 10 requirements, including the need for all parties' agreement.

5. Implement a pre-transmission amendment checklist that maps Field 77b content against all affected fields.

6. Upon receiving an MT700 with Field 77b contradictions, issue an MT799 clarification request to the issuing bank before processing the amendment.

7. Document all Field 77b-related decisions in the credit file, including the rationale for specific amendment instructions.

Conclusion

Field 77b contradictions undermine the amendment process that UCP 600 Article 10 governs. They are typically caused by incomplete amendment analysis, failure to update all affected fields, or inconsistent amendment numbering. Systematic amendment validation and cross-field consistency checks are essential to preventing these contradictions.

Frequently Asked Questions

Q1: Is Field 77b mandatory in an MT700?
No. Field 77b is optional. However, when an amendment is being issued, Field 77b should be completed with clear instructions.

Q2: How does Field 77b interact with Field 43P/43Q (Partial Shipment/Transshipment)?
If the amendment modifies shipping terms, Field 77b should reference the changes, and Fields 43P/43Q should be updated accordingly.

Q3: Can Field 77b contain multiple amendment instructions?
Yes. Field 77b can carry multiple lines of amendment content. However, each instruction should be clearly numbered and referenced.

Q4: What happens if Field 77b contradicts the beneficiary's acceptance?
Under Article 10(c), the beneficiary must accept or reject the amendment. If Field 77b contradicts the accepted terms, the beneficiary should reject the amendment and request a corrected version.

Q5: Can Field 77b be used to cancel a credit?
Yes. A credit can be cancelled by agreement of all parties. Field 77b can carry cancellation instructions, but the cancellation must comply with Article 10's requirements.

Source Notes

The following sources were consulted as context only:

• Trade Finance Global, "Understanding MT 707: Amendment to a Documentary Credit" (Feb 2024)
• Trade Finance Global, "UCP 600 – ultimate 2026 guide" (Jun 2020)
• Trade Finance Global, "ICC briefing addresses the topic of reducing discrepancy rates" (Aug 2022)
• Trade Finance Global, "SWIFT Messaging Types | TFG 2026 Guide" (Apr 2020)
• ICC, "ICC's new rules on documentary credits now available" (Mar 2023)