Sam Altman may be a billionaire and one of tech’s most influential leaders as the CEO of ChatGPT creator, OpenAI—but his communication style looks a lot like a Gen Z text chain: no capital letters, minimal punctuation, and an intentionally casual tone.

Internal text messages revealed through his legal dispute with Elon Musk show that Altman often sticks to all lowercase. This is true even at high-stakes moments, such as during the chaotic period in November 2023 when he was briefly ousted as CEO.

The stylistic choice stood in stark contrast to other tech power players in the same exchanges, like Microsoft CEO Satya Nadella and OpenAI chairman Bret Taylor, whose messages show more traditional attention to grammar and syntax.

A scroll through Altman’s social feeds today displays the same mix; some posts are formally structured, while others fail to include a single capital letter. It’s a habit he acknowledged on X back in 2023: “mildly interesting observation: i always use capital letters when writing by hand, but usually only type them when doing something that somehow reminds me of being in school.”

For the 40-year-old, the lowercase look may be a personal quirk with little professional downside, but for Gen Z workers, experts say, not being willing to spend effort holding down the shift key can carry real career consequences.

“When I see writing without capitalization it seems sloppy, unprofessional, and a little lazy,” Tara Ceranic Salinas, a professor of business ethics at the University of San Diego’s Knauss School of Business, told Fortune. “How hard is it to capitalize?”

Lowercase at work: When is the Gen Z habit actually acceptable?

If you’ve ever texted with a member of Gen Z or Gen Alpha, you’ve probably noticed that capital letters and formal sentence structure can feel almost taboo. Writing in polished prose can come across as overly intense or serious.

Young people feel comfort in the informality that communicating in all lowercase conveys—making every conversation feel like it’s with a close friend, according to Salinas. But bringing that tone straight into the workforce can backfire.

“Unfortunately, the people you work with can’t all be treated like friends, and there needs to be a bit of an adjustment in communication style,” she added.

Some young workers may already be learning that lesson the hard way. Nearly six in 10 employers say they have fired recent Gen Z hires—citing a lack of professionalism and organization and communication skills among the reasons.

The rise of remote work has further blurred the boundary between professional and personal life, making informal grammar among all generations more common on communication platforms like Slack and Teams.

“There is a standard to uphold in terms of work-appropriate conversation and showing respect to colleagues, typing “u” instead of “you” isn’t inappropriate; it’s a sign of work behavior blending into everyday behavior,” Gen Zer Zada Brown, a brand strategist at Ogilvy NY, told Fortune.

“If workers can join a meeting via the Teams app while they’re in the car driving their kid to a doctor’s appointment, using informal grammar or online acronyms doesn’t seem like such a major transgression,” she noted.

Still, workplace norms aren’t universal. At some offices, informalities flow from the top down, so it can be best to wait and see if your boss or senior leader does it first.

“If you work somewhere the CEO uses Slack, follow their lead,” Salinas said. “If they capitalize, do the same. If they use mostly emojis, emoji them right back.”

Facing a tough job market, Gen Z are breaking up with their lowercase habits

Recent college graduates are facing a more competitive job market amid economic uncertainty and rapid changes driven by artificial intelligence. That makes standing out—for the right reasons—more important than ever.

Using improper grammar in cold emails, résumés, or cover letters could mean an application lands at the bottom of the pile.

“The message it sends is that the person wasn’t willing to spend effort to hold down the shift key,” Salinas said. “From there, the potential employer may extrapolate other ideas about the individual; if they can’t do this simple thing to make an impression, what does this say about how they would behave at work?”

Some Gen Z workers appear to be taking that advice to heart already—and rethinking their digital-native habits.

“Why are we whispering? This goes specifically for texting,” one Gen Z TikToker said in a viral video about disabling auto-capitalization. “Turn it back on.”

“I just turned auto caps back on,” another wrote. “I’m officially an adult.”

Still, not everyone is on board.

“i refuse!!!!” one commenter wrote, earning more than 19,000 likes. “only if i’m sending an email or texting someone important.”