V2C is a file extension characteristic of a specialized software tool called Horizontal.Log developed by WellSight Systems. It is software used by geologists and engineers to drill wells.

A V2C file is used to store license data for this software. These are the data specifying the license type and the conditions under which the software can be used. This file is also used with license dongle for WellSight Systems products. In this way, the company protects itself against illegal use of its products.