The RWTH Extensible Training framework for Universal Recurrent Neural Networks
(RETURNN) License

The aim of this license is to lay down the conditions enabling you to use, modify
and circulate the SOFTWARE, use of third-party application programs based on
the Software and publication of results obtained through the use of modified
and unmodified versions of the SOFTWARE.

However, RWTH remain the authors of the SOFTWARE and so retain property rights
and the use of all ancillary rights.

The SOFTWARE is defined as all successive versions of RETURNN software and their
documentation that have been developed by RWTH.

When you access and use the SOFTWARE, you are presumed to be aware of and to
have accepted all the rights and obligations of the present license:

1. You are granted the non-exclusive rights set forth in this license provided
you agree to and comply with any and all conditions in this license. Whole or
partial distribution of the Software, or software items that link with the Software,
in any form signifies acceptance of this license for non-commercial use only.

2. You may copy and distribute the Software in unmodified form provided that
the entire package, including - but not restricted to - copyright, trademark
notices and disclaimers, as released by the initial developer of the Software,
is distributed.

3. You may make modifications to the Software and distribute your modifications,
in a form that is separate from the Software, such as patches. The following
restrictions apply to modifications:
    a. Modifications must not alter or remove any copyright notices in the Software.
b When modifications to the Software are released under this license, a non-exclusive
royalty-free right is granted to the initial developer of the Software to distribute
your modification in future versions of the Software provided such versions
remain available under these terms in addition to any other license(s) of the
initial developer.

4. You may distribute machine-executable forms of the Software or machine-executable
forms of modified versions of the Software, provided that you meet these restrictions:
    a. You must include this license document in the distribution.
b. You must ensure that all recipients of the machine-executable forms are also
able to receive the complete machine-readable source code to the distributed
Software, including all modifications, without any charge beyond the costs of
data transfer, and place prominent notices in the distribution explaining this.
c. You must ensure that all modifications included in the machine-executable
forms are available under the terms of this license.

5. You may use the original or modified versions of the Software to compile,
link and run application programs legally developed by you or by others.

6. You may develop application programs, reusable components and other software
items, in a non-commercial setting, that link with the original or modified
versions of the Software. These items, when distributed, are subject to the
following requirements:
a. You must ensure that all recipients of machine-executable forms of these
items are also able to receive and use the complete machine-readable source
code to the items without any charge beyond the costs of data transfer.
b. You must explicitly license all recipients of your items to use and re-distribute
original and modified versions of the items in both machine-executable and source
code forms. The recipients must be able to do so without any charges whatsoever,
and they must be able to re-distribute to anyone they choose.
c. If an application program gives you access to functionality of the Software
for development of application programs, reusable components or other software
components (e.g. an application that is a scripting wrapper), usage of the application
program is considered to be usage of the Software and is thus bound by this
license.
d. If the items are not available to the general public, and the initial developer
of the Software requests a copy of the items, then you must supply one.

7. Users must cite the authors of the Software upon publication of results obtained
through the use of original or modified versions of the Software by referring
to the following publication:
P. Doetsch, A. Zeyer, P. Voigtlaender, I. Kulikov, R. Schluter, and H. Ney,
“RETURNN: The RWTH extensible training framework for universal recurrent neural
networks”, submitted to Interspeech 2016.

8. In no event shall the initial developers or copyright holders be liable for
any damages whatsoever, including - but not restricted to - lost revenue or
profits or other direct, indirect, special, incidental or consequential damages,
even if they have been advised of the possibility of such damages, except to
the extent invariable law, if any, provides otherwise. The Software and this
license document are provided "AS IS" with NO EXPLICIT OR IMPLICIT WARRANTY
OF ANY KIND, INCLUDING WARRANTY OF DESIGN, ADAPTION, MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE.

9. You assume all risks concerning the quality or the effects of the SOFTWARE
and its use. If the SOFTWARE is defective, you will bear the costs of all required
services, corrections or repairs.

 10. This license has the binding value of a contract.

11. The present license and its effects are subject to German law and the competent
German Courts.