Do the ads on my site need to follow accessibility guidelines?

Question

Do ads that show on sites need to follow accessibility guidelines? I am a bit concerned if they do as I don't really have control over what ads are showing. Off the top of my head, I am most concerned about the really obnoxious flashy ones that I am certain don't follow accessibility guidelines.

Answer

Display ads do need to conform to WCAG guidelines. They should have appropriate alt text that starts with "Ad" or "Advertisement", they should not contain flashing that exceeds 3 flashes per second and they should be operable with only a keyboard.