I use a unique email address for every account I create on the web. I just received spam email to the unique email address I used when creating my hologram.io account:
We are pleased to inform you that you have been accepted at Hogwarts School of Witchcraft and Wizardry. Please find enclosed a list of all necessary books and equipment. Term begins on September 1. We await your owl by no later than July 31.
mktomail.com and marketo.org appear in the headers. I clipped out most of the headers and this board won’t let me post them all “new users can only put 2 links in a post”:
X-MSFBL: aG9sb2dyYW0uaW9Aam9zaGhpZ2hsZXkuY29tQGR2cC0xOTktMTUtMjE0LTQ4QGJn LXNqLTAxQDAyNC1ZRFgtMzcyOjQ3OjEwMzg6Mjc6MDozOjk6MTcwOjE1MTMy
Received: from [10.0.87.249] ([10.0.87.249:59845] helo=sjmas01.marketo.org) by sjmta16.marketo.org (envelope-from <email@example.com>) (ecelerity 220.127.116.11404 r(Core:18.104.22.168)) with ESMTP id 96/91-04010-EA9B35A5; Mon, 08 Jan
Date: Mon, 8 Jan 2018 12:34:22 -0600 (CST)
From: Mike Ryan <firstname.lastname@example.org>
To: [clipped my email]
Subject: We are so happy to have you on board!