Any living individual can sue for defamation; the dead cannot i.e. an estate or relatives of a deceased person cannot sue for libel over defamatory statements made about the deceased person.
Companies can sue if the defamatory statement is in connection with its business or trading reputation and has caused or is likely to cause serious financial loss.
An individual can normally sue in the country where the defamatory statement was read or viewed, if there is sufficient circulation, or viewers. Foreigners can and do sue in the UK, even when they are not allowed to enter the country. For example Roman Polanski, who was living in Paris, successfully sued Vanity Fair, a US publication, in England because the magazine had a limited circulation there and he was even permitted to give evidence via video link because he could not enter the UK without fear of arrest. Where a prospective defendant is not domiciled in the UK, another European Member State (or in a State which is a party to the Lugano Convention), the English Courts are not permitted to entertain a claim for libel "… unless the court is satisfied that, of all the places in which the statement complained has been published, England and Wales is clearly the most appropriate place in which to bring an action in respect of the statement." This provision was enacted to deal with the perceived problem of 'libel tourism' i.e. foreigners suing other foreigners in England because of England's perceived claimant-friendly libel laws.
A Group or Class of Individuals
A group or class of individuals, if sufficiently defined, can also sue. For example it would be defamatory to say that all strikers of a particular football team took performance enhancing drugs and each one could potentially sue, even though none had been named specifically. The larger the class of individuals defamed, the less likely unnamed individuals would be able to sue. For example, unnamed individual players could not sue on the generalised allegation that players in the Premier League took performance enhancing drugs. Similarly, individual unnamed goal keepers would not be able to sue on the generalised allegation that all professional goal keepers take 'bungs', because the class is too large.
Certain government bodies cannot bring libel claims. If, however, individual members, officers or employees are the subject of the defamatory statements, these individuals can sue personally to seek to protect their own reputations.
Sometimes television programmes/newspapers report defamatory allegations but, for one reason or another, for example because they are not confident they can actually prove the allegations, they do not identify the individual or organisation they are referring to, only giving certain details which they hope will be insufficient for viewers/readers to work out who is being referred to.
This is risky not least because, at the time of publication, there may be other information in the public domain (of which the publisher is unaware) which could lead to viewers/readers identifying the person/company being referred to. When this happens, the question of where liability for defamation lies is unclear and it is likely that the person or organisation who considers themselves defamed would attempt to sue the original programme-makers, broadcaster or newspaper that originally made the allegations.