Unless separately incorporated, wholly-owned industrial railroads are not included in the database.

It was fairly common for industries as diverse as brewing (Coors) and steel (U.S. Steel) to have operated privately-owned switching equipment on their own privately-owned tracks.

A few of those companies incorporated their rail operations separately, especially when they had isolated properties and needed to cross non-company land. Those types of companies, because they were officially separate companies, may have issued stock, even though few shares may have ever circulated among private stockholders.

The vast majority of industrial railroads were never incorporated, and therefore will never be represented by certificates. Lacking the possibility for finding certificates, there is no reason to keep most industrial railroads in the database.

I have made occasional exceptions here and there when I was uncertain whether rail ownership was officially separated or not.

Similarly, I retain a few names in the database simply as placeholders for other behind-the-scenes information. I do not expect certificates for such companies to ever appear, but peripheral paper collectibles do exist including passes, waybills, calendars, maps and so forth.