McGuire spoke on air to James Naughton, a defamation expert at Gordon Legal, and appeared to hire him to take the case. He also claimed he had hired a digital investigation firm, Asia Pacific Security Group, to trace the origins of the ad.
"Im building a case and Im going to sue their arse off," he said.
On air, Naughton advised McGuire that he appeared to have a solid case. "You certainly do have a claim. In Australia … your reputation is protected by the laws of defamation, and you can certainly bring a claim."
He suggested McGuire might claim "damage to your reputation, [that] your standing has been tarnished."
That view was backed by defamation lawyer Justin Quill, who said McGuire would have an "open and shut case" against the creators of the ad – "if he could find them and if they were within the Australian jurisdiction."
That might be a big if, though. A call to the Australian helpline for Tryvexan was answered by an operator at what appeared to be an offshore call centre. When asked where the company was based, he claimed it was headquartered in Salt Lake City, in the United States. A series of domain names related to the company are registered in Panama.
Suing Facebook – McGuires bigger target – could be even more challenging though.
"Theres a case underway right now in the High Court that might challenge this, but the law in Australia as it stands says Facebook and Google are not liable for defamatory information they carry while they dont know about it," says Quill. "But if they dont take it down within a reasonable period of being notified they could be in strife."
In this case, Facebook appears to have blocked or removed the ads quickly, which as things stand would appear to mitigate its liability.
However, says Quill, "Eddie might decide hes going to be the champion of taking Facebook on and making them a publisher thats accountable, as other publishers are, or exposing them as actually not being a publisher at all. They cant have it both ways."
As well as defamation, Perth-based lawyer Roger Blow believes McGuire could have grounds for commercial damages on the grounds that Tryvexan falsely represented him as having an interest in the company, and did so without remunerating him.
And because McGuire is such a high-profile individual, Facebook might struggle to maintain its typical hands-off stance.
"The issue Facebook could have here is how big was this and could they be expected to have had a high level of foreknowledge," Blow says. "If they knew this was likely to be defamatory, they might need to be a little more wary of Mr McGuire and his lawyers."
Should any of this actually reach the courts, Blow suggests there could be one bizarre twist McGuire might not have seen coming.
"You could argue that its 2018, and we should all be more accepting of erectile dysfunction," he says. "You could almost attack the plaintiff for saying its a negative thing."
Eddie McGuire was approached for comment but did not return calls.
Karl has been a journalist at Fairfax Media since 1999, in a variety of writing and editing roles. Karl writes about popular culture with a particular focus on film and television.
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