Using an image found online
<p>I was about to do something but got curious about the legal aspects. Say you search for an image of something, for example a famous work of architecture, because you recently visited it and want to show it to a friend in an email and an internet search returns many results. Let's say the one you like is a reduced, low resolution version of an image that is offered for sale as a larger print. Are you free to include the small digital file in an email?</p>
<p>I did some investigating and find it all confusing but the following from <a href="https://blog.shift4shop.com/using-images-legally-online" rel="nofollow noreferrer">The Complete Guide to Using Images Legally Online</a> would seem to indicate my intended use would be allowed. Agree?</p>
<p>To elaborate further, four main criteria determine whether the picture is ‘fair’ or not.</p>
<ol>
<li><strong>The purpose and character of the use</strong>: This determines whether the picture is used for a non-profit or commercial activity.</li>
<li><strong>The nature of the work to be used</strong>: For example, the laws give more freedom to factual pieces such as biographies compared to fictional work.</li>
<li><strong>The amount of the image used</strong>: The laws usually permit using a small piece of the picture or a low-resolution version.</li>
<li><strong>The market effect</strong>: Using images that do not decrease the market value of the images</li>
</ol>

<h2>Fair Use Factors</h2>
<p>Your question correctly quotes the four fair use factors from 17 USC 107. However, the explanations quoted from your source are oversimplified and a bit misleading.</p>
<p>Factor 1, for example, covers more than just whether the use is commercial or not. This is also where a court assesses whether a use is transformative. A transformative  use is much more likely to be considered a fair use. Many people misunderstand what a transformative use is in copyright law. A transformative use is not one that has been physically altered, like a track being remixed or an image morphed. Rather, a use is transformative if it is for a quite different <strong>purpose</strong> than the original. For example, suppose an image of a famous building was used as part of a marketing campaign to sell airline tickets to the city where it is located. Then someone reuses the image as part of a book on architecture. That would be transformative.</p>
<p>Factor 2 also covers whether the source work is published or not.</p>
<p>One should also note that the fair use factors apply to reuse of test, music, and other works as well as images.</p>
<h2>Analysis</h2>
<p>Let us look at the example case in the question. The image is of a famous site, and similar images are widely available. The image is at a reduced resolution, not suitable for physical printing. The intended use is for personal communication to a single person, not for sale and not for wide distribution. The use is not significantly transformative.</p>
<p>Factor 1 favors fair use somewhat, because the intended use is non-commercial. The reduced resolution helps here, somewhat. Factor 2 leans against fair use, because the image is at least somewhat creative. Factor 3 leans against fair use, because the entire image is being used, but neither 2 nor 3 is often decisive. Factor 4 is likely to be the key here, and as described there seems to be no real market harm. So this use might well be held to be a fair use if the matter ever comers up in a court, which is not likely.</p>

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