software licensing open-source-software
How to adopt a class from .Net Core?
<p>.Net Core is <a href="https://github.com/dotnet/core/blob/master/LICENSE.TXT" rel="nofollow noreferrer">licensed</a> under MIT (copy below).</p>

<p>If I understood it correctly, it says I'm allowed to copy and modify the software, including for sale, but that I have to include the license text in "all copies or substantial portions of the Software".</p>

<p>What does this exactly mean if I wanted to use (and modify) a source file from .Net Core in a closed-source project?</p>

<ol>
<li>Do I just copy the file into the project and compile it into the executable?</li>
<li>Do I have to include the license text with the compiled end-product or just in the source code?</li>
<li>Does it have to be a separate file?</li>
</ol>

<blockquote>
  <p>The MIT License (MIT)</p>
  
  <p>Copyright (c) .NET Foundation and Contributors</p>
  
  <p>All rights reserved.</p>
  
  <p>Permission is hereby granted, free of charge, to any person obtaining
  a copy of this software and associated documentation files (the
  "Software"), to deal in the Software without restriction, including
  without limitation the rights to use, copy, modify, merge, publish,
  distribute, sublicense, and/or sell copies of the Software, and to
  permit persons to whom the Software is furnished to do so, subject to
  the following conditions:</p>
  
  <p>The above copyright notice and this permission notice shall be
  included in all copies or substantial portions of the Software.</p>
  
  <p>THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.</p>
</blockquote>

<p>The source file has this written at the top:</p>

<blockquote>
  <p>Licensed to the .NET Foundation under one or more agreements.
  The .NET Foundation licenses this file to you under the MIT license.
  See the LICENSE file in the project root for more information.</p>
</blockquote>

<p>You should include the license statement or whatever you want to call it with the product in the same way that Firefox allows users to look at it's licenses, so users can identify what they are allowed to do with the software just like you want to.</p>

<p>As for the separate file part, that is up to you. They aren't telling you specifically how to use it, they just want to giving you the right to use it.</p>
