Abu Dhabi Investment Authority has dumped a 4.8% stake in Transurban Group (TCL) - the $477 million block trade was launched by UBS when the market closed on Monday afternoon. UBS lodged a substantial shareholder notice on Wednesday afternoon, which showed it had underwritten the trade on behalf of ADIA subsidiary Tawreed Investments. The block was underwritten at $6.76 a share. Transurban was trading at $6.82 on Wednesday afternoon (0.88% discount).