Qube on Sept. 8 said it would buy the Newcastle Agri Terminal for A$90 million ($65.55 million) and finished the transaction by the end of last month.
The Australian Competition and Consumer Commission (ACCC) said on Thursday that Qube did not provide enough time to review the deal as the company completed the transaction within weeks of announcing it.
"By choosing to proceed before the ACCC had a chance to conduct its review, Qube and the former owners of the Newcastle Agri Terminal are exposed to potential legal action by the ACCC," ACCC Chairman Rod Sims said in a statement.
Concerns raised by market participants include the dominance Qube would hold in the supply chain for delivery of bulk grain to the Port of Newcastle after the transaction, the watchdog said.
Qube said the agreement did not allow for a delay in finalising the deal, adding it was "disappointed" the ACCC had chosen to continue with the investigation.
($1 = 1.3731 Australian dollars)
(Reporting by Sameer Manekar in Bengaluru; Editing by Ramakrishnan M.)