The Delhi High Court on Friday ruled that WhatsApp has to delete all data on users who choose to stop using the service before Sept. 25, when the new policy takes effect. WhatsApp revised its privacy policy last month to share data with owner Facebook and allow targeted ads and messages from businesses, laying the groundwork for the free messaging service to begin making money. Students Karmanya Singh Sareen and Shreya Sethi, 19 and 22 respectively, then filed a public-interest litigation seeking to block those changes. The court also asked the telecom regulator TRAI to examine the feasibility of bringing internet messaging applications like WhatsApp under the statutory regulatory framework.Senior advocate Pratibha M Singh, who had argued on behalf of the two students, called the judgement 'path-breaking'. "It is a major dent on their policy, definitely. WhatsApp will have to make changes," she told. WhatsApp had told the court that once a user deletes an account, information and data on that person is no longer retained on its servers. It also clarified that only a user's name and phone number are shared and not the content of the messages which are encrypted.