Ikon, OMD and Mediabrands are the remaining agencies in the running for the $60m Commbank business, AdNews understands.
That development puts paid to speculation that the bank's creative agency, M&C Saatchi, might be making a full service play for the business.
It is thought that Initiative, led by Lee Leggett is the lead agency on the Mediabrands bid.
Pat Crowley is leading Ikon's bid after returning to the STW-owned firm after three months at Match Media as it bids to retain its biggest client.
Commbank spent an estimated $62.8m on main media in calender year 2013, according to Nielsen estimates.
After months of speculation, the account came into play in June.
Updated: This article has been corrected to reflect the fact that Initiative is not in the pitch, which is Mediabrands-led, according to the agency.
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