There are unconfirmed reports as many as 14 Sharks players are facing a six-month ban from the NRL.
At least six players are being monitored by ASADA officials, who began interviews with the club this week News Ltd has reported.
A short time ago, Canberra radio station 2CC reported lawyers for the Cronulla-based rugby league side were in negotiations with the agency.
The news comes just hours after betting was suspended on the Sharks round one clash with the Gold Coast Titans this Sunday.
News Ltd understood that ASADA had told Sharks officials and players this week of the extent of their involvement in the investigation, which focuses on the time sports scientist Steve Dank spent at the club in 2011, although Dank has denied any wrongdoing.
An emergency board meeting is expected to get underway shortly.
Sharks coach Shane Flanagan had declined to comment other than denying any Sharks players were interviewed by ASADA.
Meanwhile, bookmakers reacted promptly to the swirling speculation.
"There's a lot of rumour and innuendo, particularly about one side, the Sharks," Tattsbet's Gerrard Daffy said after his agency suspended games betting and a number of its futures markets.
"There's rumours a lot of players are going to be stood down, and not all from the one club."
Sportingbet Australia spokesman Bill Richmond said his agency had also stopped betting on the Sharks-Titans game.
"We stopped all markets associated with the Sharks game," Richmond said.
"We have calls from people already wanting to back the Gold Coast."