Caveats

Estimating license adoption is an inexact science. 2003 through 2005 we relied primarily on Yahoo! link: queries (Google's link: operator obtains very incomplete results). In late 2005 Google added CC queries via their advanced search page and also via their API (Yahoo! also allows this, but in this case Google's results seem more comprehensive).

Baseline numbers from specific collections

We can also know the number of works licensed at various Content Curators. The largest of these based on recent (early April 2006) for various formats may (there could easily be a larger CC-licensed video collection than Revver) be:

• Images -- Flickr -- 10.8m (was 4.1m August 2005)
• Sound -- Soundclick -- 220k (was 159k August 2005)
• Video -- Revver -- 19k (did not launch until November 2005)

License property charts

Distribution of licenses deployed. Those without 'by' (attribution) were not versioned past 1.0 (excepting public domain, which is not versioned).

Distribution of license properties across licenses deployed, e.g., 3% non-by are public domain and non-by 1.0 licenses.

Estimates over time

2006-06 -- ???

We'll publish a new estimate in June.

2005-12 -- 45 million pages licensed [1] [2]

Based on Google queries, this number was only posted to http://creativecommons.org/support/ which has since changed but is reiterated in two published Lessig interviews in January.

2005-08-09 -- 53 million pages licensed [3]

Again based on Yahoo! queries, this number turned out to be overstated as Yahoo! tuned their results estimation after growing their index.

2005-06-13 -- CC search query breakdown[4]

Breakdown of search requests and desired license properties -- people searching for video want the least freedom.

2005-05-27 -- CC in Yahoo! Advanced Search[5]

Yahoo! queries say 16m pages linking to a CC license.

2005-03-23 -- Yahoo! Search for Creative Commons[6]

Close to 14m pages link to a CC license according to Yahoo! queries.

2005-03-07 -- CC search index breakdown[7]

Breakdown of (small) CC-nutch index -- audio publishers are most permissive, video publishers least.

2005-02-25 -- License Distribution [8]

Based on Yahoo! queries there are now 10m licensed documents. Pie chart of what those licenses are.

2005-02-18 -- How many pages link to a CC license? [9]

Based on Yahoo! queries, "well over 5m." At the end of 2003 it was 1m.

2004-09-17 -- Searching for Creative Commons on Yahoo![10]

4.7m pages link to CC licenses according to Yahoo! queries.