A West Vancouver billionaire has filed a lawsuit against one of the world's largest social-media companies.

In a lawsuit naming Twitter, businessman and philanthropist Frank Giustra claims that messages posted online via the app and website are defamatory and have hurt his financial interests and relationships as a philanthropist.

“The tweets have damaged [Mr. Giustra’s] professional and personal reputation and are likely to bring the plaintiff’s character into disrepute,” reads a notice of claim.

The claim does not accuse anyone directly associated with the company of writing any of the messages in question. Instead, it says that Twitter should be held responsible because the company “neglected or refused to remove” defamatory messages from the internet.

Most of the messages listed in the lawsuit relate to Giustra’s relationship with the Clintons and conspiracy theories about Hillary and Bill Clinton and their charitable organization, the Clinton Foundation.

In the United States, the Communications Decency Act gives platforms such as Twitter and Facebook immunity from claims of defamation that reference messages that are shared on social-media services but which are written by users.

Giustra and his lawyer have however filed their lawsuit in a court in Vancouver, Canada, where the U.S. Communications Decency Act does not apply.

In an interview with the Globe and Mail, Giustra’s lawyer, Fred Kozak of Reynolds Mirth Richards & Farmer LLP, argued that Twitter is liable for the content of the allegedly defamatory messages because it acted as their publisher.

“Mr. Giustra’s aim is not in any way to censor thoughts or ideas or legitimate expression—but it does seek to prevent publication of statements which are unlawful for a variety of reasons,” Kozak told the Globe. “And we think that’s an objective that is not only consistent with society’s benefit, but also ultimately social media’s benefit.”

Giustra is the CEO of Fiore Group of Companies and founder of the Vancouver-based production company Lionsgate Entertainment. Most of his wealth was accumulated in mining and finance as well as in film. He holds a seat on the board of directors of the Clinton Foundation. Giustra graduated from Douglas College in 1979.