Police in the southern Indian city of Bangalore filed the initial charges against Amnesty on Monday following complaints that event participants called for independence of the volatile Kashmir region.
Sedition charges, which carry a maximum penalty of life in prison, have been used previously against supporters of independence for Kashmir, which is divided between India and Pakistan but claimed in full by both.
The case comes at a particularly sensitive time, with large parts of Indian-held Kashmir under curfew following weeks of deadly violence between protesters and security forces.
Security forces shot dead five people and wounded another 20 during fresh protests in the Himalayan region on Tuesday, according to witnesses and security sources.
“No Amnesty International India employee shouted any slogans at any point,” Amnesty International India said in a statement on Saturday’s event in Bangalore.
“The focus of the event was squarely on allegations of human rights violations and the denial of justice in Jammu and Kashmir.”
Rights campaigners have long accused New Delhi of using the British-era sedition law to clamp down on dissent, although convictions are rare.
The charges come as foreign charities are under intense pressure in India, with the government saying last year it has cancelled the overseas funding licences of around 9,000 non-governmental organisations in a major crackdown.
The complaints were lodged with police by a Hindu nationalist student organisation, some 200 of whose members staged protests outside Amnesty’s offices in Bangalore.
Bangalore police said they were probing the complaint and studying footage of the event at the city’s United Theological College to identify those who shouted “anti-India” slogans.