We can't keep your photos from leaving. We made them traceable instead

Starting with what we can't do

If you are hesitating over whether to put up a photo, this is the first thing you should hear.

We cannot keep your photo from leaving this service.

There are technical ways to make a screenshot harder. None of them survive someone pointing a second phone at the screen. That is outside anything we can reach.

So we don't write the words screenshot protection anywhere. If someone believed that phrase, put up a photo and then something happened to them, we would have lied to them before the incident ever occurred.

What we can do

Every photo of yours is built differently for each person who sees it.

The same photo becomes one file for the person on one side and a different file for the person on the other. A faint mark is laid over the image, and the mark differs from viewer to viewer.

So when a photo turns up somewhere, the file itself says who it was sent to. We are not inferring it. It is in the file.

The mark carries a tracing code and nothing else. No name, no phone number. Put those in and the moment the photo circulates, the contact details of the person who saw it circulate with it. We would be creating with our own hands the thing we were trying to prevent.

The photo takes a small hit

The mark covers the whole image. Keep it clear of the face and a crop of just the face carries nothing.

So your photo may look very slightly softer than it did. That is a price we pay deliberately. Given a clean photo and a traceable one, we chose the traceable one.

It is not perfect

We won't claim to catch everyone who works at removing the mark. Process an image hard enough and the mark is damaged along with it.

But the leaks that actually happen are mostly someone passing on the screen they received. Those carry the mark. And even a partial mark narrows the set of people who could have received the photo a great deal.

And we tell you

There is one mechanism stronger than any of the technology.

Most people don't take the screenshot once they know the other person will be told.

If your photo is captured, we tell you. If someone captures the same person repeatedly, we look at it ourselves. Once can be an accident. Repetition is collecting.

So it comes down to this

• We can't prevent it
• Who received a photo stays readable in the photo
• If it is captured, we tell you
• If it repeats, we act

Those four lines are everything we can hold to. If somewhere promises you more than that, it is fair to ask what the promise rests on.