He leaves Entain as the passing of legislation looms that will give TAB NZ, and Entain as its strategic partner, a monopoly in the New Zealand sports and racing betting markets.
That bill is expected to pass its third reading in Parliament in two weeks.
In announcing the departure, Entain group CEO Stella David thanked Shannon for his service.
“We thank Dean for his significant contribution to Entain and for managing the Australian and New Zealand businesses,” David said.
“The growth and integration of Neds and Ladbrokes into our global portfolio of podium position brands has been a particular highlight and he has more recently delivered what we believe is a market leading compliance programme in Australia.
“As the Australian business enters its next phase, we will continue to demonstrate our commitment to compliance and responsibly deliver great products to our customers.”
With Shannon set to depart at the end of the month, respected wagering figure Andrew Vouris has been appointed interim CEO.
Vouris brings a wealth of knowledge into the role, boasting more than 17 years of leadership experience in wagering, operations and innovation at some of Australia’s biggest wagering operators, including Tabcorp and Entain.
Vouris is widely recognised as a sharp operator with a deep knowledge of the gambling industry.
Michael Guerin wrote his first nationally published racing articles while still in school and started writing about horse racing and the gambling industry for the Herald as a 20-year-old in 1990. He became the Herald’s racing editor in 1995 and covers the world’s biggest horse racing carnivals.