Leonberger Databases

There are several databases on the web.
The International Leonberger Union doesn't keep a database.

In some countries clubs have an online database:

Czech Republic

Great Brittain

There are kennel club database in:

Austria: http://www.oekv.at/oekv/referate/zuchtbuchreferat.html
Finland:
https://jalostus.kennelliitto.fi/frmEtusivu.aspx
Italy: http://www.enci.it/libro-genealogico/libro-genealogico-on-line
Netherlands:
http://stamboek.houdenvanhonden.nl/Stamboek/Prod
Sweden:
http://kennet.skk.se/hunddata/

Two privately kept, International Leonberger database:
http://leonberger-database.com

http://ileodata.com