There's a lot of discussion over who it could be but no real leads. Initially it was assumed they were being done by a disgruntled employee but it's been a year and surely you'd get your petty revenge by stealing or breaking things if you weren't sick in the head.

The general view is of a mentally ill fetishist who blends in well enough to not come across as the type for it.

I've never seen it before and certainly haven't had company wide notices begging for someone to stop smearing excrement on the walls before.

Is this a relatively common thing in the workspace? Have you ever had similar in your job?