Learn About Zoom Hidden Watermarks Before Sharing This Meeting
Before sharing personal Zoom meeting content publicly – ideally for noble reasons – know that there are many different ways a meeting organizer can define you as a leader. This can lead to a variety of legal or professional problems.
I was a little shocked to find how easy it is to find out who in the meeting is responsible for leaking information about the meeting. While exploring the contents of my Zoom Pro account settings, I never came across Zoom’s watermarking features – mainly because they are reserved for administrators of more attractive corporate accounts. But they’re pretty powerful and I didn’t expect most people to find out about them. (Hint from The Intercept for pointing out these methods.)
There are two ways a company can use watermarks in Zoom meetings. First, the obvious: watermark your video. If the company enables this feature, then part of the user’s email address will be overlaid on the video when they watch the shared screen; Likewise, a person sharing their screen will have part of their email stuck on the video, like so:
If a company uses this watermarking feature, it will be obvious – I don’t believe you will see any warning icon. All you need to look for is hard-to-read text on your face when you share your screen. This text does not appear on the webcam stream during normal video chatting (if I am reading the Zoom manual correctly).
The second method is more insidious, and I suspect that nervous companies will use it more often than the first. This is an audible watermark and will be completely invisible to most people if they don’t know what to look for – a tiny green icon to the right of the green padlock icon in your Zoom meeting, which indicates that the feature is active.
The good news (for those with information) is that the recording should be about two minutes long, at least, to ensure that the audio watermark appears on any official meeting recordings. Less than that and you roll the dice. Your audio may have a watermark; you can do without it.
The bad news is that anything Zoom puts into sound to identify someone cannot be heard. Zoom itself is analyzing a way to watermark audio for companies. There is no magic software tool that a company could use to watermark leaked audio, and you can never be sure that you muddled up the meeting sound enough to ruin any hidden watermarks. There are too many potential opportunities .
So, if you need to sign in to an official Zoom account in order to attend a meeting and you see any watermarking tool is enabled, think twice to record and share its content, even if you are doing so from justified, moral or legal valid reason. What you share can be traced back to you, even if you think you have skillfully covered your bases.
And these are just Zoom watermarking tools. Companies have a variety of other ways to track Zoom attendees, including: looking at the devices used to connect to a meeting and comparing them to screenshots or videos captured from the meeting. checking Zoom general call participants to see who might share based on the position in which they appear on the screen; and inadvertently sharing some part of your desktop or other identifying characteristics (for example, a pop-up notification with your email address). Intercept has a pretty comprehensive list of ways potential leaks can screw up. Well worth reading.