Q: Accidental editing of shared ical through notifications?

Hello all,

Strange problem going on with a shared ical calendar. I am on Mavericks and have created a shared calendar that is going out to 4-5 different people, and is editable by all of us. 3 of us have apple products. One of the people is running Yosemite and whenever he gets an alert for the calendar, he is clicking the "close" button that appears on his desktop/laptop. Whenever he does this, I get a notification that he has changed the location of whatever event he has clicked on. He has shown me what he does and there is no way he is actually editing the event, so why am I getting change notifications?

For what it's worth, on my Mavericks Mac, I get a message that says "EVENT" changed, Location removed by xx. On my iPhone, the notification is different. It says "Location changed to _ by xx" and there is just a space instead of an underscore.

Any ideas? Has anyone seen this?