We don’t know definitively when these black and white posters first started surfacing around Louisville, but curious Louisvillians started talking about them at least a month ago.

They’ve shown up on concrete walls and telephone poles in just about every corner of the city, from NuLu to the South End White Castle. The signs — which vary in size and color — appear to be wheat-paste posters, a form of street art that’s been around since ancient times.

And once you’ve seen one, it’s kind of hard to stop seeing them after. Kind of like when you buy a new car then you start seeing it everywhere. Love this

The design of the posters translates to the name of local artist collective Often Seen Rarely Spoken. | Photo by LOUtoday

So we decided to whip out our magnifying glass — AKA our cell phone — to take a closer look. In the bottom right corner there’s a QR code that takes you to the Instagram page of local artist collective and agency Often Seen Rarely Spoken (OSRS), which solves the mystery of the simple line design.

We can only conclude that the street signs are part of a guerrilla marketing campaign for the collective that’s been painting murals locally and nationally since 2016. You might recognize their work at Waterfront Park or Lynn Family Stadium.

With that, we consider this case closed and look forward to adding it to the growing list of Louisville mysteries that keep Louisville weird.

Bonus: If you’re interested in seeing more wheat-pasted artworks, check out the Paste-Up Mural Project, an extension of this year's Louisville Photo Biennial, featuring ~60 photography pieces wheat-pasted outside galleries and businesses across Kentuckiana.