Can anyone provide some sort of official documentation stating UP will not allow foreign steam to operate on their network? I hear such all the time, but I've never seen anything other than foamer conjecture on the topic. That fact you don't see non-UP steam on UP suggests there is some reason, but I've always thought it was more a financial issue rather than an outright ban. UP might just have some insurance or technical requirement which prevents others from using their network. It is something I have come across often in my business dealings - that these things fall apart more from insurance or technical issues than policy issues. Seems like if it were a policy driven prohibition, it would be bad for UP. Not in the eyes of railfans (whose opinion has little value to UP execs) but makes them look spiteful and overly-protectionist in the eyes of shippers and no one wants to work with a jerk.