Pomerania and western part of East Prussia, i.e. so called Recovered lands, which were not so much recovered as given to Poland by Russians as some sort of compensation for lands taken from Poland in the East. those territories were not part of pre-war Poland and all of them were issued by German legal entities, so link to Poland is rather distant and indirect. Poland was not liable for compensating holders of such securities although some sort of compensation was available from West German authorities.
500 mark, 4% loan of the city of Liegnitz of 1913