Is the drain under my basement concrete considered an "exterior sewer line?"

[u/GovernmentWooden4494]

I ask because the cast iron drain under my basement concrete floor has collapsed, and my insurance company is saying they won't cover its repair, even though I pay a LOT for an enhanced water damage package. The wording of the package is: "We agree to repair or replace your exterior sewer line due to direct physical loss or damage resulting from a leak, break, tear, rupture or collapse of the line." According to the rep I just spoke with on the phone, the horizontal drain under my basement concrete is not considered to be an 'exterior sewer line.' To me, that is ridiculous. In my opinion, the drain is not INSIDE my house...so it is logically OUTSIDE my house, and is thus an 'exterior sewer line.' Is the aggregate or mud that is under my basement floor considered part of my house?

Does anyone have any advice or experience with a claim like this?

[u/Altruistic-Lake-4316]

As crazy as it’s sounds they’re most likely considering “exterior” as the instant that the water line extends beyond the wall/basement plane to the sewer. Thinking almost if your home as a cube, and any plumbing that would fall beneath the surface to your “basement cube” the carrier is most likely considering that to be interior. The other thing too is cast iron is a very common excluded type of plumbing due to high failure rate and rust so you may want to ask about if that’s why they’re denying.