VinFast Auto is trading 4.14% lower at $3.24 amid renewed concerns about Tesla’s potential entry into Vietnam. - Tesla registered a local entity in September, potentially paving the way for expansion into VinFast’s home market. - VinFast holds roughly 92% of domestic EV sales; coverage flags competition but does not explicitly link it to the September 22 decline. - The mixed market had modest technology gains, so broad risk-off sentiment does not appear to explain the decline; no new VinFast announcement was identified as a catalyst.