Altice NV and its partners are exploring a sale of about 20 percent of their U.S. cable-TV business in an initial public offering this quarter, as billionaire Patrick Drahi takes advantage of historically strong equity markets to raise cash for expansion, according to people familiar with the matter. Drahi's Altice may use the proceeds from the listing of Altice USA to help fund local acquisitions, said the people, who asked not to be named discussing private matters. Closely held Cox Communications Inc. is one potential target for Altice, one of the people said.