I recently bought a bunch of copies of the same DVD from Dollar Tree specifically for the case (Viva, single disk, clear, non-eco, no spine snaps). While unpackaging them, I noticed that each and every one has at least one horizontal slash through the spine. Typically I would think that somebody at the store was just careless with a box cutter, but these disks came from two different DT's in two different counties. Having bought them specifically for the case, I'm annoyed. Has anybody ever seen a spine slash used as a remainder mark? That's the only think that makes sense to me, short of some major carelessness in the distribution chain.

Usually remainder DVDs have the barcode on the trap sheet slashed with a fairly thick cutter, not the typical fine slit a box cutter makes. Based on your description it sounds more like an overzealous clerk cutting the shipping box open with a single cut horizontally across the spine. Usually DVDs are sent in a box of 30 units and they are placed spine-up so this would make sense that it's more of an accident.

Who knows? It could also just be an easier way to mark them rather than slashing the barcode.

I've never heard of that kind of remainder mark.

With a DVD or blu-ray, they will do something to deface the barcode -- usually a cut -- so they can't be returned or exchanged at full price.

In the old days, before barcodes became the standard for pricing stuff, they would deface things in other ways.

LPs would get a small cut of about 1/2" x 1/8" along the top; they probably just ran a saw across a bunch of boxed albums, or, less commonly, they would get a corner cut off.

Cassette tapes would have a small hole drilled into title edge of the case, or a hole drilled through the cover corner.

CDs would either get their spines cut like an LP, or a hole drilled through the barcode on the back.

Slits on the spines of DVDs and blu-rays are the result of someone overzealously opening a box with a knife.

Sounds like a clerk cut them by accident when opening the shipping container.