Those would definitly be fractional or shared. He may not realize it, but I'd bet somewhere close to his location is an OC3 node which has short OC3 lines going to a number of nearby buildings. The diagram below kind of shows it. 1,2,3,4, and 5 are all OC3 lines but are short and all connect to one main OC3. Although each has their own short OC3, they all connect to a single OC3 which leads to the local NOC. A dedicated OC3 would run all the way from only your building directly to the NOC, which generally sits on something like an OC48 backbone. Between the cost of equipment, lines, digging the trench, laying the dedicated lines, etc...it can cost millions. There's no way to get a dedicated OC3 for only $4000/month....unless perhaps you financed it and those are your monthly payments.
1__2__3__4__5
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......Full OC3....
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......Backbone...
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