[Paul F]

Phone companies and cable companies only share poles or conduits underground. They do not share cables anywhere along the path to your house. They may both use separate telephone wires in the house for phone, but that would be up to you.

Geek alert. Telecom expert spewing worthless trivia.

On poles, the telephone company cables are the lowest. Cable company cables are just above (since they came later, they got stuck between the power cables above, thereby getting the best chance of getting hit when a power cable breaks and falls, saving the telco cable).