No, it is not an error. It is not rare. It is not even very desirable. In the last year someone made a few
ebay listings calling these lines out as a 'rare'. Lines are normal and are found across all stamps in that row of a pane. The truth and reality is that most collectors avoid these stamps, they find them are less desirable and hence are valued at lower then a fully perforated stamp.
Don
Posted 10/29/2017 10:29 am
