Name change as don't want to be identifiable in any way.
I found out today from a client that one of my colleagues has done some porn work in the past and it's very publicly visible online (mostly photos, very explicit but nothing unpleasant if you know what I mean). I don't know how the client found it, but they did and now I'm wondering if I should let the owner of the company know in case other clients find it or in case they feel it reflects poorly on the company? It's not particularly well hidden, this colleague has a particular social media handle they use and it's in the title of the videos and photos so I assume found via search therefore anybody could in theory find and view it. It's not posted on their own sites or social profiles, it's third party sites so I assume they do not have control over how the content is distributed or whether it can be deleted although I could be wrong.
On the other hand...I've worked with this colleague for 2 years, they're great at what they do and are hard working, nobody's mentioned it before now so maybe it's never been noticed before, and I am leaving my role in the next month anyway so I feel like maybe it's unfair to bring this to the attention of the company founder? It's a small company, less than 50 employees, and I'm really not sure how this would be viewed by the company clients and whether the company would lose business over this. Plus I don't want to feel responsible if the colleague is fired as a result.
YABU = mind your own business, don't report it
YANBU = report it discreetly and let the company owner handle it