If an email containing a defamatory material about some person is sent to other persons or some defamatory material is published against a person on some website and all this is done to cause injury to the reputation of the person against whom the material has been published amounts to cyber defamation. Using internet as a medium to defame a person causes an irreparable loss to the injury of the defamed person as its effects are widespread and the masses that use internet have an easy access to the defamatory material published on the internet.

 The offence of cyber defamation can be divided into two categories. The first category would involve cases in which the primary publisher of the information would be liable for publishing the defamatory material. The second category would involve the cases in which the internet service provider or the bulletin board operator is made liable for the published defamatory material.
Cyber defamation is recognized a crime under the Indian Penal Code, 1860 and the Information Technology Act, 2000. Section 499 of the Indian Penal Code deals with the offence of defamation and by virtue of the enactment of the Information Technology Act also covers within its ambit the offence of cyber defamation. Sections 469 and 503 of Indian Penal Code also punish the offence of using internet as a medium to harm the reputation of other person.

 The Information Technology Act, 2000 does not specifically makes punishable the offence of cyber defamation but the act of sending grossly offensive material for causing insult, injury or criminal intimidation is a punishable under Section 66A of the Act.
In first case of cyber defamation in India, the employee of a corporate defamed its reputation was sending derogatory and defamatory emails against the company and its managing director. In this case the Court had restrained the defendant from sending derogatory, defamatory, obscene, vulgar, humiliating and abusive emails. He was also restrained from publishing, transmitting or causing to be published any information in the actual world as also in cyberspace which is derogatory or defamatory or abusive of the plaintiffs.
In another case, accused posted obscene, defamatory and annoying message about a divorcee woman and also sent emails to the victim. The offender was traced and was held guilty of offences under section 469, 509 IPC and 67 of IT Act, 2000.
A person can lodge a complaint alleging commission of the offence of cyber defamation to the Cyber Crime Investigation Cell.