Can I legally decompile my own binary code created by copyrighted compiler?
<p>I've the following scenario:</p>

<p>I've written some programming code which I own, but I lost the source code, however I've binary which was created by the compiler.</p>

<p>Can I simply decode my own binary code back to the source code if I know how to do it?</p>

<hr>

<p>Here are the technical details to reproduce that scenario on the computer:</p>

<ol>
<li><p>Write a dummy program:</p>

<pre><code>$ echo "void start() { }" &gt; foo.mq4
</code></pre></li>
<li><p>I've downloaded the compiler (without accepting any agreement):</p>

<pre><code>$ curl -O https://download.mql5.com/cdn/web/metaquotes.software.corp/mt5/mql.exe
</code></pre></li>
<li><p>Compile the program (which generated encrypted <code>foo.ex4</code> binary file):</p>

<pre><code>$ mql.exe /mql4 foo.mq4
MQL4/MQL5 Compiler build 1162 (02 Jul 2015)
Copyright 2001-2015, MetaQuotes Software Corp.
foo.mq4 : information: Compiling 'foo.mq4'
Result: 0 error(s), 0 warning(s)
</code></pre></li>
<li><p>I lost my source code:</p>

<pre><code>$ rm -v foo.mq4
removed ‘foo.mq4’
</code></pre></li>
<li><p>I'm trying to decompile the binary file using a tool to recover my source code:</p>

<pre><code>$ ./decompiler foo.ex4
</code></pre></li>
</ol>

<p>Is that perfectly fine to do that, or not? Or it depends, if so, on what?</p>

<p>I certainly don't see why this would not be legal. If you wrote a novel in English and paid someone to translate it into Spanish you could translate it back if you want.</p>

<p>The copyright scenario is they have copyright in the compiler; you own the copyright in the input and output of it. The compiler's creators have no claim on the output because there is none of their creativity in it.</p>

copyright licensing eula