Company no longer exists in 2018.

Source Wikipedia

"2017: Tesoro announces that it will be changing its name to Andeavor following its acquisition of Western Refining.[14] On August 1, 2017, the company changed its ticker symbol to "ANDV" from "TSO".

2018: Andeavor announces that they have entered into a definitive merger agreement with Marathon Petroleum Corporation under which Marathon Petroleum will acquire all of Andeavor's outstanding shares. The merger was closed on October 1."