UPDATE 1-U.S. SEC reviews short-selling, equity swap rules after GameStop, Archegos sagas Reuters 5/5/2021 By Katanga Johnson WASHINGTON, May 5 (Reuters) - The U.S. securities regulator is considering measures to boost transparency around "short-selling" and equity derivative bets and to rein-in retail "gamification" following January's GameStop saga and the meltdown of Archegos Capital, its new chair planned to tell lawmakers. Gary Gensler, sworn in last month as chair of the Securities and Exchange Commission (SEC), will testify before the House of Representatives Financial Services Committee on Thursday. Democratic progressives have pressured him to take a tough stance on Wall Street after January's Reddit-fueled GameStop rally and last month's collapse of New York investment fund Archegos exposed weaknesses in SEC rules.