A short but valid warning here further to a cease and desist letter sent out by German company Komsa to a web based company with whom they had taken some advertising space. It turns out that Komsa's own ad-blocker software replaced any web adverts on the site with its own logo. Komsa got upset as the powers that be thought their logo was being used without their authority. You can imagine the red faces when the web site company pointed this out to them!