The fact that WhatsApp has been locked down for years makes this news even more newsworthy.
The social network has faced several lawsuits in the past, but none have led to a major legal battle.
The case in the US involving WhatsApp is one of the first that has reached the court.
In 2016, the Federal Communications Commission ordered Facebook to remove WhatsApp from its mobile platform because it does not comply with a legal requirement to keep users informed about its network.
Whatsapp was not one of many apps in the Apple App Store that the company was blocking in 2016.
It is not yet clear if this is the case for all apps.
In February 2017, the European Commission announced it had closed the case against WhatsApp.
This means that the European court will not hear any new legal cases against the app.