Dollar Bill Serial Number Two Different Colors

That's kinda cool. On the new LEPE presses, the left and right serial numbers are printed separately, because the new computerized numbering blocks are so large that they can't be crammed together close enough to print all the serial numbers on a sheet in one pass. I checked my error guide and there's no mention of any incidents similar to this. Post it on Facebook to the US Error Note Collectors group and maybe Fred Bart will see it and comment.

Interesting, first time I've seen this.

I've got plenty of 1988 $1 notes and none of the serial numbers are as dark as that left side serial number on the OP's note. If you have an example @Grushna, I'd sure like to see it.