BlueFreeway paid £2.5m for a 51% stake in Holler in 2007, with an agreement to buy the rest of the agency over a three-year period.
Earlier this year BlueFreeway was delisted from the Australian Stock Exchange after breaching banking covenants following an acquisition spree.
The terms of Holler's buy back deal have not been disclosed.
Holler, which has offices in London and Sydney, plans to move into broadcast services and aims to invent products and formats that it would share on a part-ownership basis with other creative partners.
James Kirkham, managing director at Holler Digital, said: "After an eventful two years in which we have further cemented our position at the forefront of digital strategy in the UK, we're hugely positive about the future and our ability to drive plans forward, taking Holler even further.
"Our ambitions are focused on partnering with the right people, having made great strides at originating content and new format ideas."
This article was first published on brandrepublic.com