A reaction which seems to consistently accompany viewings of the hit movie The Social Network goes something like this: "Er, can't they get sued for that?" The "they" being the producers of the movie and the "that" being the unauthorized (and presumably unflattering) portrayal of real-life individuals such as Facebook founder Mark Zuckerberg.
The question of potential legal claims in the United States arising from the movie has been canvassed by John Schwartz in the New York Times ("No Stopping Movie View of Mark Zuckerberg"), by Eriq Gardner at THR, Esq. ("How Mark Zuckerberg could sue over 'Social Network'") and, in a detailed treatment of the various issues, by Aaron Moss, also at THR, Esq., in "Everything you need to know about 'The Social Network' and the law". The consensus of the three articles could be summarized as follows: under US law, because public figure plaintiffs are required to prove that the defendant published their defamatory statement with "actual malice", a defamation claim would be highly unlikely to succeed; there's a better (but still not great) chance of a publicity rights-based claim to succeed; and non-legal considerations (such as the magnified and continued attention that a lawsuit would itself cause) mean that lawsuits are relatively unlikely to arise.
To what extent is the analysis different if undertaken in Canada? For our purposes, let's not change any of the relevant facts: we're talking about the extent to which Mark Zuckerberg, a US resident, can sue in Canada based on a movie which was released in Canada.
Defamation. Unlike the US, Canadian defamation law does not recognize a separate category of "public figure" plaintiffs, and there is no requirement that plaintiffs prove that the defendant acted with actual malice (or any other kind of malice). From that perspective, much like defamation law in England, Canadian defamation is comparatively plaintiff-friendly. But a plaintiff could not simply sue anybody in a Canadian court - the courts would be unlikely to host a lawsuit wherein Mark Zuckerberg tried to sue the screenwriter, director or Hollywood studio responsible for the creation of the film, since none of them are resident in Canada. However, he could potentially bring an action in Canada against the Canadian distribution company which has licensed the rights to distribute the movie in Canada. Canadian courts will assess a number of factors in determining whether there is sufficient "connection" between plaintiff, defendant and publication (or, in this case, screening of the movie) to warrant using the Canadian courts as a forum for a claim (see, e.g., Van Breda v. Village Resorts Limited (2010), 98 O.R. (3d) 721 (C.A.), leave to appeal to S.C.C. granted,  S.C.C.A. No. 174; Bangoura v. Washington Post, 2005 CanLII 32906 (ON C.A.); Black v. Breeden, 2010 ONCA 547 - the foregoing cases all deal with cross-border internet publications, but set out the relevant tests for when Canadian courts should assume jurisdiction). In the case of a movie distributed in Canada by a Canadian entity, there likely would be sufficient grounds for a court to assume jurisdiction. That being said, jurisdiction is not the only consideration: a plaintiff would need to assess whether the statements or depiction contained in the movie actually rise to the level of "defamatory", whether any defences are applicable (truth/justification; fair comment) and whether the comparatively low level of damages awarded in Canada will warrant the monetary investment needed to commence a defamation action.
"Personality"-based common law actions. As compared to the United States, Canadian common law is under-developed when it comes to causes of action which protect the intangible interest in the commercial use of one's "personality" or "image". Under the name of "appropriation of personality", Canadian courts have developed a tort which seeks to protect plaintiffs where their name, image or likeness has been used in a commercial context and where that use has some sort of "endorsement" connotation (for further details and sources, see this earlier Signal post and this article by Jill Jarvis-Tonus and Meghan Dillon)). While the precise contours of the tort are somewhat unclear, the decision of the trial court in Gould Estate v Stoddart Publishing Co ((1996), 74 CPR (3d) 206 (Ont Ct Gen Div), aff’d (1998), 39 OR (3d) 545 (CA), leave to appeal to SCC refused (1999), 236 NR 396 (note) (SCC)), in trying to address the interface between image protections concerns and freedom of expression concerns, drew a distinction (sometimes referred to as the "sales vs subject" distinction) between use of an image which sought to capitalize on that image in order to drive sales of a product or service and a use where "the subject of the activity is the celebrity and the work is an attempt to provide [the public with] some insights about that celebrity". In other words, where a defendant is using someone's image in order to talk about that person because there is a public interest in knowing more about them (as compared to using that person's image to, say, sell a car) then there may be a defence made out against the claim. Of course, that distinction isn't entirely air-tight: when it comes to a movie about Mark Zuckerberg, his likeness is being used both to sell a product (ie to sell tickets to the movie) and to provide information about him. But given the interest in promoting freedom of expression, it is likely that a court would privilege the latter purpose.
"Personality"-based statutory actions. Three Canadian provinces (British Columbia, Saskatchewan and Manitoba) have legislation in place which seek to protect individual's from having their image or likeness used in the promotion of goods or services - but such protection seems unlikely to extend to the sort of use entailed in a fictional movie. Likewise, while the Quebec Charter of Human Rights and Freedoms provides that protection of an individual's image is encompassed in a right of privacy, it is unclear (if unlikely) that such a right extends to the portrayal of a person by another individual (since such a portrayal is not a use of the person's "image" in any meaningful sense). Finally, while the Quebec Civil Code provides that use of a person's image or likeness can be an invasion of privacy, it is qualified by an allowance for providing "legitimate information to the public". None of the provisions in question have, to my knowledge, been assessed by courts in the context of a "docudrama" motion picture and so the extent of any protection they may offer remains speculative.
Thus, in Canada, an assessment of the potential actions available to Mark Zuckerberg is likely the opposite of that which obtains in the United States: a defamation claim (assuming that there is anything defamatory in the movie) would be the most plausible claim, while other personality-based torts are less obviously available (largely because the requirements for successfully bringing such a tort claim are so undefined). What is entirely consistent on both sides of the border, however, are the extraneous, non-legal considerations, about which I'll borrow the words of Aaron Moss:
Legal issues aside, as is often the case, public figures need to weigh the benefits of bringing a lawsuit against unwittingly providing free publicity to a film they probably don’t want you to see. And there’s always the public relations backlash that any celebrity contemplating major litigation should take into account. All of which probably explains why, rather than filing a lawsuit, Mark Zuckerberg spent the week "Social Network" opened visiting Oprah and donating $100 million to New Jersey public schools.