Google doesn't ban duplicate pages.

They can't can they? Is this another webmaster myth?

[internetheaven]

Everytime someone has posted a message that said 'avoid duplicate pages' or 'duplicate pages are considered spam' I would nod my head a little and say (quietly) Yeah, that sounds reasonable.
Then today I had a thought - you can't ban duplicate pages.

If Google banned duplicate pages then a devious webmaster (which I generally tend to think like) would simply create several carbon copies of their competitors which would get them either banned or seriously dropped in ranking.
I checked and there are many terms for which their are hundreds of pages of almost identical content (only differences being a short intro and a couple of links). You can check yourself, the easiest way is to search for tutorials as there are thousands of 'copy and paste' duplicates of each.

All those who have been bashing on about duplicate pages being banned for so long, have I misunderstood you? As far as I can see, Google can't remove pages that are duplicated as they can't always be sure that they are not removing the original. The only way around it is to judge the duplications purely on inbound links.

[g1smd]

>> stripey, your not really contributing to the discussion just trying to point out flaws in my poor site migration planning. <<

Actually, I thought that it was one of the best posts in the thread.

.

Google does remove duplicate content. There are several ways that it is done, and different timescales.

If you have two different domains with the same filenames and same content, Google will initially list them both but then soon quietly hide one of them (Google's choice), so use a 301 redirect to say which one you want listed.

In some cases, the listing is still available by using &filter=0 on the end of the Google search URL, but eventually the number of those gradually drops too. There are over 2000 sites using ODP data. However, you can only ever find a few of those sites in most Google searches. Removing the filter lists a lot more, but by no means lists all of them by a very long way.

If you put the same page of content on many pages of the same site, then Google would reduce the listing to one entry quite quickly. However, sometimes it can overlook things. I am aware of a page on a site that appears 4 times in the listings (out of only 45 results though), where the dynamic URL has print-fiendly and other options available:

www.xxzxx.xx.uk/Rs/Fs/Pu/sml00B.asp
www.xxzxx.xx.uk/Rs/Fs/Pu/sml00B.asp?Tx=1
www.xxzxx.xx.uk/Rs/Fs/Pu/sml00B.asp?Pf=1
www.xxzxx.xx.uk/Rs/Fs/Pu/sml00B.asp?Pf=1&Rs=1

Another similar page used to have 7 copies listed, but 6 months later is now down to two.