At what point can a computer-generated file infringe copyright?
<p>In general it is illegal to download a copyrighted file without paying the copyright owner.</p>

<p>But is having <a href="https://en.wikipedia.org/wiki/Torrent_file">metadata (hash)</a> of the copyrighted material legal? </p>

<p>What if I've run a program (like <a href="http://thatsmathematics.com/blog/archives/102">Mathgen</a>) that generates random documents and at some point it generated the copyrighted material?</p>

<p>Another example: my program generated a two-line program extracted from pi that by chance (or perhaps not) is copyrighted (like <a href="http://www-01.ibm.com/support/knowledgecenter/SSLTBW_2.1.0/com.ibm.zos.v2r1.ieab500/hpropr.htm">IEFBR14</a> which has around 10 words).  Does my program's output infringe that copyright?</p>

<p>Copying is illegal, creating an identical work by coincidence isn't. If it is not a criminal case, then a court decides whether it is more likely that the identical work was created by copying or by coincidence. Creating an identical work through a random process isn't going to happen, claiming this would be an awful defense. On the other hand, it is quite possible that two software developers using very stylized code adhering to struct coding conventions can produce quite large bits of identical code.</p>

<p>Your links titled "metadata" and "hash" don't actually link to a description of metadata, or the description of a hash, but to a description of torrent files, which is something totally different. Systematically distributing files whose only purpose is the illegal duplication of copyrighted works should not be done without consulting a lawyer, as has been said on other threads (whether posting links to copyrighted files is legal). </p>

<p>The chances that a random process will generate a file identical to an existing copyrighted file of say over 100 bytes are virtually zero. If there is an illegal copy of a copyrighted file, and you claim that you created it through a random process and coincidence, you will lose, and deservedly so. </p>

copyright software