India had asked the US to help in serving papers to the executives of 11 internet companies who are accused of hosting content designed to fuel communal hatred.
"As you know, there are limits to our Constitution's protections on free speech, such as when the speech comprises a true threat or incites imminent violence. In this case, there has not been a sufficient showing in this regard," US authorities said in response.
The case was filed in December 2011 by a journalist named Vinay Ray who said internet firms should be prosecuted for hosting the content.
In January this year, the court issued fresh summons for the executives and asked the Ministry of Home Affairs to ensure they were delivered.
The case will be heard in Delhi on May 21.