What Will macOS 10.16 Be Called: Mammoth, Monterey, Skyline, or Something New?

Every year heading into WWDC, one question on many Mac fans' minds is what Apple will choose as the name for the next version of macOS. The tradition dates all the way back to the beginning of Mac OS X with its big cat names, and then in 2013 Apple shifted to Calfornia-themed names with the unveiling of OS X Mavericks.

macos 10 16 names
Back in the early days after the debut of OS X Mavericks, we discovered a total of over 20 California-themed trademark applications filed by various limited liability companies that were all but certain to be shell companies created by Apple to hide its identity.

Over time, some of the trademarks like Yosemite, Sierra, and Mojave were indeed used by Apple for its major Mac operating system updates, while trademark applications for many of the other names have been abandoned.

In last year's lead-up to WWDC 2019, we noted that of that original set of trademark applications, only four unused ones remained active: Mammoth, Monterey, Rincon, and Skyline. All four of those trademarks had been granted by the U.S. Patent and Trademark Office, and Apple was keeping them alive for potential use by filing successive extension requests.

Trademark recipients have up to 36 months from the date of approval to file a Statement of Use proving they are using the trademark in commerce, although they are required to file for extensions every six months during that period to keep that full window open.

Apple of course opted to name its 2019 macOS release Catalina, which wasn't one of the previously trademarked names, but in case Apple has opted to go back to its original list, we decided to check back on last year's trademark list to see if any of them remain protected.

Of the four, Rincon is no longer active, having been abandoned in September 2019 after its 36-month window expired. The other three remain active for now, with Apple's presumed shell companies continuing to file extensions as needed.

  • Mammoth, which is likely related to Mammoth Lakes and Mammoth Mountain, a popular area for skiing and hiking in the Sierra Nevada mountains, saw its trademark application approved in March 2019, and a second extension of the Statement of Use period was approved in March 2020. The full 36-month window won't expire until March 2022 as long as additional extensions continue to be filed.
  • Monterey, a historic city and popular vacation spot on the Pacific coast, has long been one of the most popular macOS name options among our readers over the years. The trademark was applied for by Asilomar Enterprises LLC in December 2013, but wasn't allowed until June 12, 2018. A fourth extension to Statement of Use window was granted just last week, and Asilomar will have until June 2021 to prove commercial use of the name, provided a final extension is requested in December of this year.
  • Skyline likely relates to the scenic Skyline Boulevard that largely follows the ridge of the Santa Cruz Mountains running south from San Francisco, and Antalos Apps LLC filed for a trademark on the name in December 2013. The trademark was allowed on March 20, 2018, and the fourth Statement of Use extension was granted in March of this year. The owner will have until March 2021 to prove use of Skyline in commerce, provided all necessary extensions are requested.

So what will macOS 10.16 be called? Mammoth, Monterey, and Skyline all seem like reasonable options, but we've also seen Apple turn to names that had not been previously rumored. In years when the new macOS version is viewed as more of a refinement of the previous version rather than a leap forward, Apple has used names that bear relationships to the previous ones, such as going from Yosemite to El Capitan and Sierra to High Sierra.

With macOS 10.16 again seeming to be more of a refinement release, could we see something like macOS Channel Islands (the island group that Catalina is a part of) or macOS Avalon (the only city on Catalina)? Or with Apple reportedly set to begin transitioning to its own Arm-based chips for its Mac lineup, could it shift gears to something completely different? Whatever it ends up being, we'll know one week from today.

Related Forum: macOS Big Sur

Popular Stories

iPhone 17 Pro in Hand Feature Lowgo

iPhone 17 Pro Coming Soon With These 14 New Features

Friday July 4, 2025 1:05 pm PDT by
Apple's next-generation iPhone 17 Pro and iPhone 17 Pro Max are just over two months away, and there are plenty of rumors about the devices. Below, we recap key changes rumored for the iPhone 17 Pro models. Latest Rumors These rumors surfaced in June and July:Apple logo repositioned: Apple's logo may have a lower position on the back of the iPhone 17 Pro models, compared to previous...
Apple Watch Ultra Night Mode Screen

Apple Watch Ultra 3 Launching Later This Year With Two Key Upgrades

Wednesday July 2, 2025 1:13 pm PDT by
The long wait for an Apple Watch Ultra 3 appears to be nearly over, and it is rumored to feature both satellite connectivity and 5G support. Apple Watch Ultra's existing Night Mode In his latest Power On newsletter, Bloomberg's Mark Gurman said that the Apple Watch Ultra 3 is on track to launch this year with "significant" new features, including satellite connectivity, which would let you...
iPhone 17 Pro in Hand Feature Lowgo

iPhone 17 Pro Max Battery Capacity Leaked

Thursday July 3, 2025 5:40 am PDT by
The iPhone 17 Pro Max will feature the biggest ever battery in an iPhone, according to the Weibo leaker known as "Instant Digital." In a new post, the leaker listed the battery capacities of the iPhone 11 Pro Max through to the iPhone 16 Pro Max, and added that the iPhone 17 Pro Max will feature a battery capacity of 5,000mAh: iPhone 11 Pro Max: 3,969mAh iPhone 12 Pro Max: 3,687mAh...
airpods pro 2

AirPods Pro 3 to Help Maintain Apple's Place in Earbud Market Amid Increasing Low-Cost Competition

Thursday July 3, 2025 7:25 am PDT by
Apple's position as the dominant force in the global true wireless stereo (TWS) earbud market is expected to continue through 2025, according to Counterpoint Research. The forecast outlines a 3% year-over-year increase in global TWS unit shipments for 2025, signaling a transition from rapid growth to a more mature phase for the category. While Apple is set to remain the leading brand by...
iphone 16 pro models 1

Here's How the iPhone 17 Pro Max Will Compare to the iPhone 17 Pro

Saturday July 5, 2025 1:00 pm PDT by
Apple should unveil the iPhone 17 series in September, and there might be one bigger difference between the Pro and Pro Max models this year. As always, the Pro Max model will be larger than the Pro model:iPhone 17 Pro: 6.3-inch display iPhone 17 Pro Max: 6.9-inch displayGiven the Pro Max is physically larger than the Pro, it has more internal space, allowing for a larger battery and...
apple silicon mac lineup 2024 feature purple m5

Apple's Upcoming Macs Listed in New Report

Thursday July 3, 2025 9:09 am PDT by
AppleInsider's Marko Zivkovic today shared a list of alleged identifiers for future Mac models, which should roll out over the next year or so. The report does not reveal anything too surprising, but it does serve as further evidence that Apple is seemingly working on new models of every Mac, including the MacBook Air, MacBook Pro, iMac, Mac mini, Mac Studio, and Mac Pro. Apple is...

Top Rated Comments

jayducharme Avatar
66 months ago
Mac OS Cluster****
Score: 40 Votes (Like | Disagree)
MakeAppleAwesomeAgain Avatar
66 months ago
I don't care as long as they don't release new features and just focus on getting macOS stable again.
Score: 40 Votes (Like | Disagree)
nfl46 Avatar
66 months ago
macOS Snow Catalina

?
Score: 39 Votes (Like | Disagree)
TheSkywalker77 Avatar
66 months ago
macOS High Catalina.

Unoriginal joke, I know.
Score: 33 Votes (Like | Disagree)
Lounge vibes 05 Avatar
66 months ago

MacOS Weed
Yeah, because after a year with Catalina, Weed is what we need
Score: 22 Votes (Like | Disagree)
casperes1996 Avatar
66 months ago
I'm hoping for macOS Redwood
Score: 21 Votes (Like | Disagree)