Facebook, now Meta Platforms, submitted before a bench of Chief Justice Satish Chandra Sharma and Justice Subramonium Prasad that CCI cannot investigate it in a "creeping fashion".
Senior advocate Mukul Rohatgi, appearing for Facebook Inc, contended that just because Facebook is the formal owner of WhatsApp and the instant messaging platform is said to share its data with the parent company does not mean that it is a necessary party to the probe.
"The ground that WhatsApp will share something with me is no ground to initiate investigation against me," he submitted.
"The fact that WhatsApp can share items with certain people does not mean they could all be the necessary parties. These policies are not my policies. Whether it breaches the right to privacy is to be seen but merely because they share it with X, Y or Z is not a ground to investigate me," he said.
During the hearing, senior advocate Harish Salve, representing WhatsApp, submitted that they were not challenging the investigation but the challenge was to CCI's jurisdiction to probe the matter.
The arguments on behalf of WhatsApp, Facebook Inc, and Facebook India concluded and the court will hear the submissions of the counsel for CCI on July 28.
It had said that there was "virtually a stay" on the proceedings and the anti-trust regulator must be allowed to carry out its investigation and Facebook and WhatsApp must be asked to file their replies.
On January 3, a bench headed by then Chief Justice DN Patel extended the time for filing replies by Facebook and WhatsApp to two CCI notices of June 2021 asking them to furnish certain information for the purpose of inquiry conducted by it.
The court, on Thursday, had orally observed that "there was no stay order" concerning the probe and opined that the two companies should file their reply before CCI.
A lawyer appearing for the appellants had said that their appeals would become infructuous if the interim protection is taken away and informed that a preliminary reply has already been filed before CCI.
WhatsApp and Facebook had subsequently challenged before the single judge CCI's March 2021 order directing a probe against them, saying that the issue concerning its new policy was already pending consideration before the high court and the Supreme Court.
The single judge on April 22 last year, however, refused to interdict the investigation directed by the CCI.
The CCI had contended before the single judge that it was not examining the alleged violation of individuals' privacy which was being looked into by the Supreme Court.