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Among her friends, 30-year-old Molly Weissman is known as Molly Weissman. Her colleagues at her office in New York refer to her in conversation as Molly Weissman, and when you ask her how she’d like to be named on second reference in a news story, she opts for “Weissman” there too. But on Facebook, ever since she got married in 2015, Weissman is Molly Lister Weissman—a nod to the fact that before her marriage, she was known among friends, and on all her official ID documents, as Molly Lister.

Weissman, the media director for the nonprofit Global Citizen Year, legally changed her last name to match her husband’s shortly after their wedding. “It was important for both me and my husband that our family just have one name,” she says. But still, she wanted to be “findable.” She didn’t want her new name to pop up on the computer screen of a friend or acquaintance who didn’t know she’d gotten married and be totally unfamiliar. “If I had just been ‘Molly Weissman,’” she says, “they might be like, ‘I don’t know that person.’”

For people in English-speaking countries who’ve aged out of their teen years and into adulthood in the age of Facebook, it’s a familiar phenomenon—the brief moment of bewilderment that ensues when an unfamiliar name pops up on one’s Facebook timeline, intruding like a complete stranger into a space that’s usually full of friends. Often, it’s a somewhat common female first name coupled with an unfamiliar last name; “Who is this?” you might ask yourself, only to click through to her profile page and discover an old classmate you remember fondly but haven’t spoken to in a while, recently married to someone you’ve never heard of.

This is likely less common among Facebook users in countries and cultures where women aren’t traditionally expected to legally change their family names upon marriage to a man. But it happens in the United States, and it’s precisely why Allison Schaffer, who works at an advertising firm in Chicago and is still in the process of legally changing her last name to match her husband’s, opted for “Allison Schaffer Gonzalez” over “Allison Gonzalez” on Facebook. It's also why Jessica Wagner, a high school teacher in Minnesota, opted for “Jessica Buckingham Wagner” on Facebook—so that her old friends who’d known her in her single life would recognize her name when she reached out to reconnect online. Chicago speech therapist Hannah Rodheim, too, was well aware of the phenomenon when she switched from “Hannah Rodheim,” her legal married name, to “Hannah Newman Rodheim” on Facebook. (Though in her case, she tells me, it was partly so that her husband’s cousin who’s also named Hannah Rodheim and she would stop receiving each others' messages.)

It’s not a terribly complicated problem for friends of a newly married woman to solve, all told; it usually takes just a minute of detective work to unravel the mystery of her identity. But the unhyphenated double surname some women have adopted online to prevent that confusion is a naming custom heretofore more often seen in textbooks and foreign countries. And, it's popularizing another option for women's last names when they marry men, beyond just “keep,” “change,” or “hyphenate.”

There’s a long tradition—in some places—of women using their family name from birth in addition to a husband’s family name. Some prominent American women in literature, politics, and society have been known to go by a married name tacked on after their original or “maiden” names, sans hyphen:  Coretta Scott King, Elizabeth Cady Stanton, Harriet Beecher Stowe, Sandra Day O’Connor, Ruth Bader Ginsburg, and Hillary Rodham Clinton, to name a few. In Russia and in many Spanish-speaking countries, it’s customary for a woman to retain her family or father’s name when she takes her husband’s family name (see: former president of Argentina Cristina Fernández de Kirchner); women in Turkey, Iran, China, and certain Balkan countries have been known to adopt this format too. Still, according to Laurie Scheuble, a Penn State professor who researches marital naming, while rates of women doing anything non-conventional with their last names after marriage have risen slightly in the last two decades, some 90 percent of women who get married to men still adopt their husband’s last name when they marry.

Historically, the primary reason women have gone by two last names without a hyphen is because “these are women who are more established in their career, very educated. So they do that to maintain their identity,” Scheuble says. And some see this strategy as offering a distinct advantage over hyphenating: “As a society, we tend to ignore hyphens,” she adds. “We don't like them; they're cumbersome.” (Several of the women I spoke to for this story said they found hyphenated double last names to be clunky or excessively long.)

Today, in many lines of work, one’s professional reputation is inextricably tied to one’s Google search results. Molly Weissman, for example, who changed her middle name to Lister when she changed her last name, published some work as a journalist before her marriage. In addition to using both last names on Facebook, she sometimes refers to herself as Molly Lister Weissman in more formal online settings, too, such as her outgoing work-email signature, so her current work retains some identifiable link to her old articles. Scheuble refers to women like Weissman, who change how they introduce themselves depending on context, as “situational last-name users.” Even some famous double-surname users who ostensibly kept their maiden names to maintain professional recognizability after marriage, have been known to go by different names in different situations. Sandra Day O’Connor has been known to go by "O'Connor", her husband’s last name in colloquial settings, while Hillary Rodham Clinton has generally gone just by "Clinton" in her campaigns for political office. Scheuble also points to Kim Kardashian West as a recent example, who started going by two surnames in some contexts after her marriage to Kanye West, but uses only her maiden name in her handles on Instagram and Twitter.

Of course, one of the many ways in which social media has altered humans’ social interactions is by making casual friendships much easier to maintain over wide distances, and much easier to pick back up after long periods of dormancy—making social recognizability just as important to many women as professional recognizability.

Danielle Tate is the founder of MissNowMrs.com, a site offering guidance to women changing their names after marriage—a sort of “TurboTax for name changing,” which is often described as a tedious process. According to Tate, including both a birth surname and a married surname boosts a woman’s chances of being found online by people looking for her, a concept she calls “personal SEO” (search-engine optimization), so she’s not surprised to have noticed more women incorporating a maiden name into their Facebook and social-media presences informally. But Tate has also observed an uptick, specifically in the last 18 months or so, in women seeking guidance as to how to change their legal names to include two last names, no hyphen.

“Two last names without a hyphen is very much a trend right now,” Tate says, and adds that starting around 2012, women replacing their middle names with their maiden names has been “a big, big name-change trend,” particularly in the South. Both formats, she says, are particularly popular among highly educated women with established careers at the time of marriage. She ascribes that popularity to the fact that this format offers more flexibility than hyphenating. Hyphenated names are “like Krazy Glue,” she says, in that the names have to remain stuck together virtually everywhere: Women who hyphenate have to sign all legal documents with their hyphenated last name, and often feel more obligated to introduce themselves with both last names colloquially—and that, Tate says, can be “a mouthful.”

A lawyer I spoke to, Greta Mattison Megna (née Mattison), has two last names on Facebook because she has had two legal last names since getting married in 2016; similarly, third-grade teacher Alyssa Postman Putzel (née Postman) has adopted what’s sometimes known as a “double-barreled” last name since getting married last summer. Both women appreciate the recognizability it affords them online and in professional contexts; Mattison Megna felt her maiden name was “part of her identity,” and says she and her husband, a physician, briefly considered the possibility that he might take her name, but decided against it because his professional recognizability was important, too. They considered just about all the options before settling on her double surname, she adds.

Even if she hadn’t gone with two legal surnames, though, Mattison Megna says, she would’ve listed herself as Greta Mattison Megna on social media. “All my friends, everyone I’ve known my whole life, knows me as Mattison,” she says. At the same time, there’s “a small chunk of people,” too—her husband’s friends, or people she and her husband meet together in their new hometown of Minneapolis—who’ll more likely type “Greta Megna” into the search box when they look her up on Facebook.

While tech has contributed to the popularity of the unhyphenated double surname in the United States, tech is also in some ways standing in the way of it becoming a commonly accepted naming format. Scheuble says she’s come across legal and administrative forms designed to enter last names into databases that can only register a single or hyphenated surname. “You can put a hyphen, but you cannot put a space,” she says. Scheuble recently tried to help her niece who has an inherited double-barrel last name apply for grad school. “God knows where she ended up” within some schools’ administrative systems, Scheuble says. “It’s ridiculous that computer systems make decisions about people’s lives. But that’s what happens.”

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