The Land Matrix dataset is a public database of large-scale land deals. It provides records documenting land deals since 2000.

As of April 2012 the data available represents about 50% of the entire data base. The remaining deals are being crosschecked and added, together with new data provided, on an on-going basis.

The Disclaimer and License page links to terms and conditions. The only specific reference to a license therein (which seems to be for entire website and not just database) is within No contract section where it states:

... Furthermore, the coordinators of the Land Portal may add, change, improve, or update the information of the website without notice and may in its sole discretion alter, limit or discontinue part of this site or deny at its sole discretion any user access to this site or any portion thereof.

For more information, see Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.

This license is, of course, not open as per the http://OpenDefinition.org/ due to its non-commercial restriction.