Bradley, who is 64, wrote that he and his wife, Katherine, recently realized that their three sons were not interested in media ownership, and so they would have to look “farther afield” for a next generation of Atlantic leadership. Bradley reported to his staff that he and his advisers had compiled a list of 600 potential investors, but ended up approaching only Powell Jobs as a potential partner. The parties did not disclose the final sale price or valuation of Atlantic Media.

Powell Jobs (53), the widow of Apple founder Steve Jobs, founded Emerson Collective in 2004. The organization, based in Palo Alto, California, invests in both nonprofit and entrepreneurial efforts to bring about immigration and education reform, and is focused on a host of other issues as well. Emerson Collective also has significant investments in media, from movie-production companies such as Anonymous Content to start-ups such as The California Sunday Magazine. The organization has also provided support to several nonprofit journalism outlets, including the Marshall Project and ProPublica.

In a statement, Powell Jobs noted that Ralph Waldo Emerson, a co-founder of The Atlantic, inspired the name and the mission of her organization. She praised The Atlantic for the breadth and scope of its purpose: to “bring about equality for all people; to illuminate and defend the American idea; to celebrate American culture and literature; and to cover our marvelous, and sometimes messy, democratic experiment.”

Powell Jobs is not the first person associated with the technology industry to enter the legacy journalism market in Washington, D.C., where The Atlantic is now based. In 2012, Facebook co-founder Chris Hughes bought a controlling stake in the New Republic, an investment that held great initial promise but soon soured. More auspiciously, the Amazon founder Jeff Bezos bought the ailing Washington Post in 2013 and quickly invested, with significant success, in its journalism and in its digital reach.

Powell Jobs’s investment in The Atlantic comes at a fragile time for advertising-supported media. Facebook and Google now take in more than half of all mobile-advertising revenue. According to the tech and media analyst Mary Meeker, those two companies’ ad revenue is growing faster than the rest of the market’s combined, squeezing publishers. And many of the most quickly growing brands are fueled not by advertisers, but by venture-capital firms that can sustain large short-term losses in an uncertain media landscape.

Unlike both the New Republic and The Washington Post, The Atlantic is not ailing at the time of this sale. According to the company’s president, Bob Cohn, the privately held company is profitable, and has seen marked growth in audience and revenue in recent years. The magazine’s print circulation has been increasing, even as the industry average has declined. The publication’s website audience has grown 36 percent in the first half of 2017 alone, drawing a record 42.3 million visitors in May. Over the past decade, the company has worked to diversify its revenue sources. In 2006, 85 percent of The Atlantic’s revenue came from print advertising and circulation. This year, print will account for less than 20 percent of incoming revenue; the company’s digital, events, and consulting divisions make up the remaining 80 percent. In the past decade, the company’s annual revenue has quadrupled, to nearly $80 million.