Letter of Credit Forum

If each set consists of three originals (i.e there is an indication on each one such as 1 of 3 originals etc) each one should bear stamp and seal. 

If you are referring to the rider or attachment to each original BL, i.e each original consists of three pages, then, provided that the attachments can be seen to be related to the BL ( and this can be evidenced by stating the BL number on each page) this would be sufficient, and would not require a a stamp and signature of the carrier on the 2nd or 3rd page. However, in some cases where the BL number is not mentioned on the 2nd or 3rd page, some carriers will fold the corners of the attachment and put a seal across the adjoining pages to signify authentication of all the attachments.

The relevant ISBP paragraphs are below:

26. Unless the credit or a document provides otherwise, pages which are physically bound together, sequentially numbered or contain internal cross references, however named or entitled, are to be examined as one document, even if some of the pages are regarded as an attachment. Where a document consists of more than one page, it must be possible to determine that the pages are part of the same document.

27. If a signature or endorsement is required to be on a document consisting of more than one page, the signature is normally placed on the first or last page of the document, but unless the credit or the document itself indicates where a signature or endorsement is to appear, the signature or endorsement may appear anywhere on the document.