Nats demand 'risks rating'; Seven's $320m buyback will hand Stokes majority control; Lehman woes rattle global markets; Sinosteel talks Midwest chief into leaving, eyes 13.2pc stake; Dollar sinks below 80 US cents

Nats demand 'risks rating'; Seven's $320m buyback will hand Stokes majority control; Lehman woes rattle global markets; Sinosteel talks Midwest chief into leaving, eyes 13.2pc stake; Dollar sinks below 80 US cents