Joby Aviation Inc.'s stock JOBY rose 8% after the maker of electric air taxis said it has received a $100 million investment from SK Telecom Co. Ltd. SKM, a day after the firm got closer to commercial passenger flights and secured approval from U.S. regulators for its first electric vertical takeoff and landing, or eVTOL, aircraft. Proponents contend that eVOTL aircraft are quieter and safer to operate than internal-combustion-engine helicopters. The leading telecoms firm in South Korea is now making an equity investment in the company as part of an expanded partnership between the two. The deal, which was signed by Joby on June 27th, paves the way for Joby to participate alongside SKT in Korea's K-UAM Grand Challenge, Joby said in a statement. The Challenge is a phased demonstration program, led by Korea's Ministry of Land, Infrastructure and Transport, to foster the adoption of aerial ridesharing in Korea, it said. The S&P 500 SPX has gained 14% in the past year and the stock has gained 167%.