Not-quite railroad companies

In this project, legitimate railroad companies are defined as those that intended to transport freight or passengers for profit. (Salesman samples of fictitious companies are also allowed because those certificates are indistinguishable from genuine certificates.)

A few types of companies are disallowed, regardless of the fact that they might be rail-related and regardless of the fact that some use full-scale, genuine equipment:

• Historical societies and rail museums - A few operate genuine locomotives and rolling stock on closed-loop track or leased track. Some have even issued "stock certificates." Regardless of their equipment, none are considered genuine railroad companies.
• Amusement parks - Over the last century, numerous amusement parks have carried visitors on closed loop track, ranging in scale from 1-foot to standard gauge. None are considered genuine railroad companies. (Examples include Disneyland Park Railroad (California) and Dollywood Express (Tennessee.)
• Airport trams - Several large airports have operated trams, with some on genuine rails. All seem to have been municipal operations and none are known to have issued certificates. All closed-loop operations like this are excluded.

There are, of course, companies that operate in gray areas. Some are included and some are excluded on a case-by-case basis.

• Tourist trains - Tourist railroads and dinner trains are known in practically every state and many are rather famous – Cass Scenic Railroad (West Virginia), Virginia & Truckee Railroad (Nevada), White Pass & Yukon Railroad (Alaska) and the Cumbres & Toltec Scenic Railroad (Colorado). Most operate genuine equipment over genuine rails and own rights-of-ways across lands that are not their own. Operations over at least one (the Royal Gorge Route in Colorado) is controlled, but not operated by a main line company (Union Pacific). While none of these companies are currently known to have issued certificates, they would definitely be included in this database if any appear.