Ero Copper is trading 5.1% lower at $35.92, with no clear company-specific announcement or overnight catalyst explaining the September 28 move. - Bank of America’s September 25 stake purchase is prior context, not an explanation for Monday’s decline. - Nasdaq futures are down 0.88% and S&P 500 futures 0.40% amid technology weakness and renewed Iran-related tensions. These factors may add pressure, but evidence does not establish them as the cause.