还是刚问您的信用证,保险规定是：marine insurance policy or certificate,in du

还是刚问您的信用证,保险规定是：marine insurance policy or certificate,in duplicate,
接上面,in negotiable form,endorsed in blank,covering marine risks as per I.C.C.(all risks),I.W.C.,I.S.R.C.C.clauses,from warehouse to buyer's warehouse,irrespective of precentage,with claims payable in Italy.
是不是也要保险单后面盖shipper公章,被保险人写shipper是吗?