The listening device hidden in the All Blacks hotel suite in Sydney may not have belonged to the opposition.

The bug was found sewn inside a chair during a routine security sweep of the room.

AUT associate professor of sports management Geoff Dickson said it was more likely to be the work of a gambling syndicate.

He said they had a large amount of money, and the information gained would allow them to push it in the right direction.

He said the cost of getting caught would be catastrophic for anyone associated with the Australian Rugby Union.

A private investigator said it was not uncommon for sweeps to be made of hotel rooms before important guests arrived, but it is uncommon for something to be found.

Director of Thompson and Toresen, Daniel Toresen said it was extremely rare to find a bug during a security sweep.