By the time I had found out that companies could watch and track my cyber movements, I had already acquired the 'eyes' of 122 companies, all of which were watching me via Facebook. I imagine a similar number are watching you too, monitoring your purchases and general surfing activities. But fret not at the invasion of privacy! There is a way to cull this intrusion and pluck their 'eyes' out. The following instructions will allow you to neutralise them...for awhile. But you will need to go back and perform some maintenance every 2 months or so.
Go to the facebook help centre here https://www.facebook.com/help/568137493302217.
Pick the correct global region...I'm in the UK so I pick European Interactive blah, blah. The current split of the world is Europe, Canada and the US. When you select the region you live in, you will be brought to a page called 'Your Online Choices'. Here you select the specific country you are based. Pick the appropriate country.
The next page brings you a collection of blue squares. Select 'Your Ad Choices' and behold! Now see how many companies are watching you and more importantly what options you have to close their prying eyes.
I currently have 105 companies watching me...time for a purge.