Dallas, Texas-based Southwest Airlines Co (NYSE:LUV) has sold US corn-stover-to-ethanol technology company SAFFiRE Renewables LLC, <a href="https://renewablesnow.com/news/southwest-expands-push-into-saf-with-takeover-of-saffire-853407/" target="_blank">which it took over</a> less than two years ago as part of its sustainable aviation fuel (SAF) use strategy.