Ad Placement _ TOS - two issues

few policies to be discussed

[Sobriquet]

In [google.com...] we see two Ad Placement points.

1) Up to three ad units may be displayed on each Web site page, but no ad unit shall contain any advertisement in common with any other ad unit. Serving two or more identical ads on a single page constitutes double-serving, which Google does not support.

2)No Google ad may be placed on pages published specifically for the purpose of showing ads, whether or not the page content is relevant.

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Now, in point 1 ( above ) I gues the ads are self fed by Adsense Code. How does the publisher have control over an advt not repeating in the page ( double serving?)

In POint 2( above ). I guess what do we mean by pages specifically for the purpose of showing ads, wheter or not page content is relevant. How practical is this? We see lots of popular sites which get good targeting of google ads.. are they not TOS breakers?

[jetteroheller]

Point 2 is a rubber paragraph which can be applied to any site with no real content.

[Atomic]

Does #1 mean you can't stack skyscrapers on the left or something like that which is a very popular practice? Does each ad format have to be unique?