Although most Facebook users did not share any fake news articles during the 2016 U.S. presidential campaign, a new study reveals that the small number who did were mostly Americans over the age of 65. The findings suggest the need for renewed attention to educate particular vulnerable subgroups, such as those over the age of 65, about fake news. So-called fake news - false, misleading information that appears to resemble a news article - gained prominence during and after the 2016 U.S. presidential election, and scientists have raised concerns about fake news' spread and its influence over public discourse. However, much remains unknown about the mechanics behind the spread of fake news during the election. To shed light on the individual-level characteristics associated with sharing false articles, Andrew Guess and colleagues disseminated an online survey to 3,500 people in three different waves throughout the 2016 U.S. presidential campaign. Of the respondents, 1,331 of the initial wave agreed to share their Facebook profile data, which allowed the authors to link their survey responses to the respondents' Facebook sharing history during 2016. The shared articles were then cross-referenced against a curated list of fake news domains, including a list created by Craig Silverman of Buzzfeed News. The results showed 90% of these users did not, in fact, share articles from fake news domains with their Facebook friends, and only 8.5% shared one or more fake news articles. Most of the sharers (18%) were both self-identified Republicans over the age of 65, the authors discovered, and these individuals shared nearly seven times as many fake news articles (.75 on average) than respondents in the youngest age group, those ages 18 to 29.