File This Under Kinda Creepy

I remember when EFF first pointed these out four years ago. The printers still do it - be aware.

EFF's "Yellow Dots of Mystery" on Instructables | Electronic Frontier Foundation:

it's deeply troubling that printer manufacturers implemented this surveillance mechanism under the table after secret meetings between government representatives and technology manufacturers. Printer companies don't disclose the tracking to their customers and so the existence of these yellow tracking dots remains secret.