Vintage Star Wars Comic Question

[jedimarvin]

I recently acquired a collection of Marvel Star Wars comics. They were are all in excellent NM condition. However several of the comics from the 20-30ish range had a black line drawn diagonaly through the UPC code at the bottom of the cover. I assumed the previous owner had done this for some reason so I ordered four of those issues again from an online dealer. Two of the comics I recieved didn't have the line and two of them had the same black line. What does that mean? Is it some wierd variation? Does this decrease the value of the comic? Any help on this would be appreciated.

[Ji'dai]

I would guess that those issues were reported to the publisher as unsold by the retailer for credit.

Normally when this happens retailers remove the entire cover. Publishers usually warn consumers about buying books without covers since they are reported as unsold by the retailer; thus publishers (and the author) didn't receive royalties from the sale.