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Yes, this is correct. While a preferred format for this particular sequence ID is defined in the ST.26 DTD, it is not generated by the tool. In fact, there is a verification rule that ensures that this element is not present in the XML. This field is intended for the use of IP Offices which exchange sequence listings with database providers only and not for data communicated between IP Offices. For further details see Annex V of WIPO Standard ST.26.
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