End User License Agreement


We’re using these definitions:

  • “Yenka Software” means the object code form of the Yenka client and server software, including content and executables;
  • The “Yenka Product(s)” means those aspects of the Yenka Software for which you have been granted a valid licence by us or one of our authorised representatives;
  • “Yenka Download” means the file downloaded from the Yenka website that is used to install the Yenka client software.
  • “You” or “your” means the person or organisation who intends to use the Yenka Software;
  • “Us”, “we” or “our” means Sumdog Ltd (previously Crocodile Clips Ltd), of 43 Queensferry Street Lane, Edinburgh EH2 4PF, Scotland;
  • A “Computer” is a workstation, terminal or other device on which the output of the Yenka Software can be displayed.
  • “Students” means the students or pupils that are registered at an educational establishment.
  • The “School Roll” is the total number of, full-time or part-time, Students that are registered at an educational establishment. This includes those who do not use the Yenka Software.
  • “Remote Teaching” means teaching a student who is not at the same postal address as the teacher.


Please make sure that you are happy with these terms before you use the Yenka Software. By using the Yenka Software, you’ll show that you accept these terms. Provided you accept these terms, Sumdog Ltd grants you a limited, non-exclusive licence to use the Yenka Product(s). This Licence Agreement replaces any earlier end-user licence agreements.

Multiple-Site and Remote Teaching

Unless agreed in writing with Sumdog Ltd, this Licence Agreement does not permit the use of the Yenka Product(s) at multiple postal addresses or for Remote Teaching.

Licence Types

The ways in which you’re allowed to use the Yenka Products are governed by the type(s) of licence(s) you’ve been granted for those products:

Concurrent User Licence

A Concurrent User Licence permits employees and students of a school to use the Yenka Product(s) on a specified number of computers at a time, all located at a single postal address.

Site Licence

A Site Licence permits employees and students of a school to use the Yenka Product(s) on all Computers located at a single postal address. Unless agreed in writing with Sumdog Ltd, a Site Licence is not valid for very large schools (School Roll more than 2000).

Home Licence

A Home Licence permits the owner of the e-mail address used to register the licence, to use the English language version of all Yenka Product(s) on a single Computer, at his or her private home address.

A Home Licence does not permit use:

  • in certain countries;
  • in any school or organisation;
  • in the residences associated with boarding schools; or
  • for commercial purposes, such as private tutoring or training.

However, a Home Licence does permit use for non-commercial home-schooling.

The Home Licence is granted at our sole discretion, and we reserve the right to terminate your licence and hence your use of the Yenka Products at any time.

Commercial Licence

A Commercial Licence lets you use the Yenka Product(s) on a specified number of Computers at a time at a single postal address.

General Terms

With any of the licence types listed above, you can:

  • make a copy of the Yenka Download, but only for backup purposes;
  • share models, screen-shots & printouts created by you using Yenka, except for commercial publication.

However, you are not allowed to:

  • make any other copies, or distribute or make available any copies at all, of the Yenka Download;
  • rent, lease, loan, sub-license or distribute the Yenka Software, or otherwise use it for commercial gain;
  • broadcast the output from the Yenka Software beyond your home or organisation;
  • reverse engineer, decompile, disassemble or modify the Yenka Software, or any part of it;

The Yenka Software, and all of the files and intellectual property associated with it, is entirely owned by Sumdog Ltd and its licensors. It is protected by international copyright law and applicable national laws.

For licences which have been purchased, we warrant that the Yenka Software will perform substantially in accordance with our pre-sale descriptions for a period of ninety days from purchase. Our entire liability, and your only remedy, shall be, at our sole discretion, either the return of the price you paid or a replacement delivery of the Yenka Software to you. This limited warranty is void if the failure of the Yenka Software is a result of an accident, abuse or misapplication. Online content is no longer available as of 1 December 2022.

To the maximum extent permitted by law, we disclaim all other warranties, either express or implied, including but not limited to implied warranties of merchantability and fitness for a particular purpose with regard to the Yenka Software and accompanying materials.

To the maximum extent permitted by law, we shall not be liable for any other damages whatsoever arising out of the use or inability to use the Yenka Software, even if we have been notified about the possibility of such damages.

If you do not comply with any of these terms and conditions, we may terminate this Licence to use the Yenka Software.