The Constitution and its amendments binds the government, not private entities such as corporations.

The Fourth Amendment gives you zero protections from corporations willingly handing your data over to the government upon a simple warrantless request. A corporation can choose to tell the government to pound sand without a warrant, but they're not in any legal way obligated to do so.

EDIT: Actually, I may be wrong here. The Electronic Communications Privacy Act of 1986 may give you some protections against data intended to be private, such as Friends-only social media posts, private messages, etc.