License Declaration Comment

[torao]

What license declaration should be added to the Go source files we created and add to Tendermint? For reference, the sources of Tendermint currently have no comment on the license.

A suggestion in Issue #12.

[zemyblue]

I think the way of following link is good. https://softwareengineering.stackexchange.com/questions/157968/how-to-manage-a-copyright-notice-in-an-open-source-project

In summary, how about adding our license if add a new file, and updating the license if modify the TenderMint file and adding changes if possible.

[syleeeee]

I have consulted with the patent team, and here is a summary and the details.

Summary

• Original file - keep the original copyright notice
  • but lots of files don't have a copyright header.
• Modified file - add modification info
  • If there's no copyright header when you modify it, please add it.

Modified work Copyright {year} LINE Corp. 
Original work Copyright 2016 All in Bits, Inc
        
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
        
    http://www.apache.org/licenses/LICENSE-2.0
        
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

(I'm still not sure about the copyrighted year.(Copyright 2016 All in Bits, Inc) I'll get back to you after having more investigations.)

• New file - add LINE's copyright header

Copyright {year} LINE Corp. 
    
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
    
    http://www.apache.org/licenses/LICENSE-2.0
    
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

Details

Licensing of line/tendermint

• The new tendermint(https://github.com/line/tendermint) would be a copyrighted work by LINE Corp.
  • we should edit LICENSE
• And the original tendermint(https://github.com/tendermint/tendermint) would be a part of the new tendermint.

Details of Apache license v2.0

in a perspective of the original tendermint, (because we should comply with what original author licensed)

• Based on section 1. Definition,
  • the original tendermint is a Work.
  • the new tendermint is a Derivative Works.
• Based on the section 4. Redistribution,
  • open-sourcing the new tendermint is a redistribution since LINE will distribute copies of the Work and the Derivative Work.
  • We must do the followings when we publish this repo.
    • include a copy of the License; and
    • state that we changed the files;
      • the thing is there's no specific way how to write the notice.
      • Although writing original copyright and modified copyright together is not a common way in the intellectual property world, it's commonly used in the open source world.
        • for example, Chromium, linux and kubernetes
      • retain the same rights that we've got from the original work. (such as copyright, patent, ...)
  • It says "You may add Your own copyright statement to Your modifications and may provide additional or different license terms and conditions .... of Your modifications".
    • Therefore we'll make the new tendermint Apache-licensed by LINE Corp.

---

Please feel free to let me know if you have any other ideas.

[zemyblue]

Thank you for your research. Now became clear.
As your opinion, I think it is good to use next three type.

• Original file - keep the original copyright notice
• Modified file - add modification info
• New file - add LINE's copyright header

And we need to modify LICENSE of origin tendermint.
We'll modify it as your suggestion. and we'll request the review to you. Please check it later. @syleeeee