In 2011 Max Schrems, a law student in Vienna, used his right under EU law to ask Facebook for everything it held on him. What came back was a CD of PDF files, 1,222 of them, covering about three years of his use of the site.
The file held things he had deleted. Among them were messages about a friend's health that he had removed from his account. Deleting them on the site had not deleted them from Facebook's servers.
He filed 22 complaints with Ireland's Data Protection Commissioner, where Facebook's European business is based, and a 23rd after the Snowden disclosures in 2013. Those complaints started a decade of cases that went as far as the EU's highest court.
What it shows
You can't know what a company holds on you until you ask. The file is often longer than you'd guess, and it can include what you believed you had removed.
For your own record
Ask each company you use what it holds, from the email address the account uses. Keep the date you asked and the date they answered. If the answer includes something you deleted, that's the next thing to ask about.