united-states copyright software
Do I need permission to reimplement application programming interface calls/classes?
<p>Suppose MS Excel has an API so that other programs can communicate with it. Suppose I'm the developer of OpenOffice Calc, and I want other programs to be able to communicate with my program in like manner. So, for example, let's say Excel's API has a function called "run" and takes a formula as an argument. Calc's API would then also have a function called "run", which takes a function as an argument. Is that legal?</p>

<p>My opinion is that the copying of a single API endpoint, "run" that takes a function as an argument is not infringement.</p>

<p>I can think of several lines of argument that get to this same conclusion:</p>

<ul>
<li><strong>Originality</strong>: It doesn't exhibit the modicum of creativity required by the <em>originality</em> test. (<em><a href="https://supreme.justia.com/cases/federal/us/499/340/case.html" rel="nofollow">Feist</a></em>)</li>
<li><strong>Short phrases doctrine</strong>: It is a short word or phrase, which both the copyright office (<a href="http://www.copyright.gov/circs/circ34.pdf" rel="nofollow">Copyright Office Circular</a>, <a href="https://www.law.cornell.edu/cfr/text/37/202.1" rel="nofollow">37 CFR 202.1</a>) and courts (e.g. <em><a href="http://caselaw.findlaw.com/us-federal-circuit/1102853.html" rel="nofollow">Hutchins v. Zoll</a></em>) have declared ineligible for copyright.</li>
<li><strong>Merger</strong>: The merger doctrine allows reuse of an expression if it is one of only a very few number of ways of expressing an idea. I can't think of many other ways to express a function intended to run a function other than with the verb "run".</li>
<li><strong>Scènes à faire</strong>: It is not infringement to use an expression if it has become standard, stock, or common in a particular setting. Naming a function "run" is common in the programming community.</li>
</ul>

<p>Any one of these alone would be enough to rule out copyright infringement by taking this individual component of Excel's API.</p>

<hr>

<p>Note: Whether merger and scènes à faire are part of the originality/copyrightability analysis or part of the infringement analysis is not uniform across circuits. For example, the 6th circuit considers both merger and scènes à faire part of the copyrightability analysis. But, the 2nd and 9th circuits treat them as part of the infringement analysis and in the 9th circuit, they are affirmative defenses.</p>
