Lots of people are looking for a Twitter alternative after Elon Musk bought the social media site last month, changed the site’s rules on impersonation, fired half of the site’s staff, and announced plans to sell “blue check” verification badges for $8 per month.
One of the fastest growing alternatives is Mastodon, which looks and feels a lot like Twitter.
But Mastodon isn’t a Twitter clone. It’s a free open-source platform, originally launched in 2016 by developer Eugen Rochko, and it’s made up of many different instances, or servers, instead of being managed by one company on one domain name.
This makes signing up and getting finding your friends a little bit harder.
There are also strange little quirks as well. Tweets are called “toots.” Retweets are called “boosts.” Because it’s an open-source project, it doesn’t have the same level of polish as social media sites like Twitter that are owned and operated by professionals.
Emails and loading can be slow. It’s a little bit like using Linux versus Windows or MacOS.
Mastodon has been growing fast. In the 12 days after Musk bought Twitter, Mastodon app downloads on Apple App Store and Google Play for Android surged more than 100 times previous rates to 322,000 installs during the period, according to analysis by Sensor Tower, an app analytics firm.
On Nov. 7, Mastodon founder Rochko tooted that there were over 1 million monthly active users of the service. That’s still a lot lower than the over 245 million daily active users of Twitter that CEO Elon Musk tweeted about this week.
Here’s what you need to know about Mastodon:
First, you need to pick a server, or instance
Because anyone can set up their own Mastodon server, there’s no central place to sign up like twitter.com. You have to find a server to sign up for. They’re known as “instances,” and you can think of them like e-mail providers.
A user on one instance can interact with users on other instances, including following, replying, and boosting. All instances taken together are called “the fediverse.” (The term comes from “federated,” which refers to the loosely connected way the servers work together — again, similar to email.)
Each instance has its own URL, which comes after your username, sort of like an email domain. There are over 5,000 instances, according to a site tracking Mastodon use, and they often follow a particular theme, such as geographical region or topic. Some require you to fill out a short application form with information like your interests or why you want to join that instance. Some servers are small and only for a small handful of friends.
There’s even a quiz that you can take to find which instance might be right for you.
The most popular instance is mastodon.online, which is also administered by the service’s founder. Bigger instances mean many of the best or shortest usernames on the server have already been taken. There’s also a list of instances you can join on Mastodon’s website.
Unlike Twitter, many of the instances that Mastodon runs on are not-for-profit, and some raise money for server costs and other expenses on sites like Patreon. It’s possible that some instances could stop operating because their administrators lose interest.
All instances have a feed just for people on that server that shows all toots posted in that instance in chronological order. But you can also just look at your personalized feed, which shows only toots from the people you follow — that’s the experience that’s most like Twitter.
Your username includes your server’s name
Following isn’t as simple as it is on Twitter. If you want to follow someone on the same instance as you, press the plus button next to their username.
But if they’re on a different instance than you, it’s best to copy and paste their entire username into Mastodon’s search box— including the part after the second “@” symbol that denotes which server they are on.
For example: @Gargron@mastodon.social is how to follow the CEO of Mastodon. Users who are not on Mastodon.Social need to copy and paste that entire string into their search box.
There’s no verification on Mastodon, and DMs are viewable by the instance administrator. Content moderation is also up to the instance administrator — Mastodon.Social, for example, bans Nazi imagery. Other servers may have looser rules.
How to find friends
Mastodon can be a bit of a ghost town when you first log on, but there are a few ways to find your old favorite tweeters on the platform. Whether they post a lot is a different question.
One of the easiest ways to find people to follow is to search “Mastodon” on Twitter, where people who have created new accounts often post their new handles. Copy and paste it into the Mastodon search box to follow them.
You can also copy and paste your Mastodon handle — with the @ symbol and domain — into your Twitter account to get your existing followers to try to join you.
There are several directories that list interesting people to follow on Mastodon.
If you’d like to try to follow the same people on Mastodon as you did on Twitter, there are several third-party apps that will try to import your follow list, although they require access to your Twitter account — be aware that you’re giving that information away to a third party.
Get tootin’
It’s time to get tooting. A first post that describes your interests or topics can help people find you.
Mastodon, like Twitter in its early days, gives users the choice to use different apps and interfaces to interact with toots and boosts.
Twitter migrants who miss TweetDeck, which displays several timelines on a desktop computer, should enable the Advanced Web Interface option in the settings to bring up a denser interface with multiple columns.
There are also several apps for iPhones and Android devices that work regardless of which instance you’re on. The main Mastodon apps work well, but there are lots of alternative clients.
Make sure to look through the settings for features that aren’t available on Twitter — like automatic post deletions and powerful block and muting features. A sensitive content feature can hide rants or NSFW posts behind a button. The latest version of Mastodon, 4.0, includes new abilities to follow hashtags, translate or edit posts, and additional content filters.
If you don’t like the instance you started on, it’s possible to export your account to another server.
Mastodon isn’t as easy to use as Twitter, nor does it have as many users generating content that will bring you back day after day. But its free, open-source approach with thousands of different servers guarantees that the platform can’t be bought for $44 billion.
Peter Thiel, co-founder of PayPal, Palantir Technologies, and Founders Fund, holds hundred dollar bills as he speaks during the Bitcoin 2022 Conference at Miami Beach Convention Center on April 7, 2022 in Miami, Florida.
Marco Bello | Getty Images
Founders Fund, the venture capital firm run by billionaire Peter Thiel, has closed a $4.6 billion late-stage venture fund, according to a Friday filing with the Securities and Exchange Commission.
The fund, Founders Fund Growth III, includes capital from 270 investors, the filing said. Thiel, Napoleon Ta and Trae Stephens are the three people named as directors. A substantial amount of the capital was provided by the firm’s general partners, according to a person familiar with the matter.
Axios reported in December that Founders Fund was raising about $3 billion for the fund. The firm ended up raising more than that amount from outside investors as part of the total $4.6 billion pool, said the person, who asked not to be named because the details are confidential.
A Founders Fund spokesperson declined to comment.
Thiel, best known for co-founding PayPal before putting the first outside money in Facebook and for funding defense software vendor Palantir, started Founders Fund in 2005. In addition to Palantir, the firm’s top investments include Airbnb, Stripe, Affirm and Elon Musk’s SpaceX.
Founders Fund is also a key investor in Anduril, the defense tech company started by Palmer Luckey. CNBC reported in February that Anduril is in talks to raise funding at a $28 billion valuation.
Hefty amounts of private capital are likely to be needed for the foreseeable future as the IPO market remains virtually dormant. It was also dealt a significant blow last week after President Donald Trump’s announcement of widespread tariffs roiled tech stocks. Companies including Klarna, StubHub and Chime delayed their plans to go public as the Nasdaq sank.
President Trump walked back some of the tariffs this week, announcing a 90-day pause for most new tariffs, excluding those imposed on China, while the administration negotiates with other countries. But the uncertainty of where levies will end up is a troubling recipe for risky bets like tech IPOs.
SpaceX, Stripe and Anduril are among the most high-profile venture-backed companies that are still private. Having access to a large pool of growth capital allows Founders Fund to continue investing in follow-on rounds that are off limits to many traditional venture firms.
Thiel was a major Trump supporter during the 2016 campaign, but later had a falling out with the president and was largely on the sidelines in 2024 even as many of his tech peers rallied behind the Republican leader.
In June, Thiel said that even though he wasn’t providing money to the campaign for Trump, who was the Republican presumptive nominee at the time, he’d vote for him over Joe Biden, who had yet to drop out of the race and endorse Kamala Harris.
“If you hold a gun to my head, I’ll vote for Trump,” Thiel said in an interview on stage at the Aspen Ideas Festival. “I’m not going to give any money to his super PAC.”
From left, U.S. President Donald Trump, Senator Dave McCormick, his wife Dina Powell McCormick and Elon Musk watch the men’s NCAA wrestling competition at the Wells Fargo Center in Philadelphia, Pennsylvania, on March 22, 2025.
Brendan Smialowski | Afp | Getty Images
Meta on Friday announced that it was expanding its board of directors with two new members, including Dina Powell McCormick, a part of President Donald Trump’s first administration.
Powell McCormick served as a deputy national security advisor to Trump from 2017 to 2018. She is also married to Sen. Dave McCormick, a Republican from Pennsylvania who took office in January.
“He’s a good man,” Trump said of McCormick in an endorsement last year, according to the Associated Press. Powell McCormick and her husband were photographed in March beside Trump and Tesla CEO Elon Musk, a current advisor to the president, at a wrestling championship match in Philadelphia, Pennsylvania.
Additionally, Powell McCormick was assistant Secretary of State under Condoleezza Rice in President George W. Bush’s administration.
Besides her political background, Powell McCormick is vice chair, president and head of global client services at BDT & MSD Partners. That company was founded in 2023 when the merchant bank BDT combined with Michael Dell’s investment firm MSD. Powell McCormick arrived at the firm after 16 years at Goldman Sachs, where she had been a partner.
Her appointment represents another sign of Meta’s alignment with Republicans following Trump’s return to the White House.
In January, the company announced a shift away from fact-checking and said it was bringing Trump’s friend Dana White, CEO of Ultimate Fighting Championship, onto the board. The changes follow Trump dubbing the company behind Facebook and Instagram “the enemy of the people” on CNBC last year.
Also on Friday, Meta said Patrick Collison, co-founder and CEO of payments startup Stripe, was also elected to the board. Stripe was valued at $65 billion in a tender offer last year.
“Patrick and Dina bring a lot of experience supporting businesses and entrepreneurs to our board,” Meta co-founder and CEO Mark Zuckerberg said in a statement.
Zuckerberg visited the White House last week, after attending Trump’s inauguration in Washington in January. Politico last week reported that the Meto CEO paid $23 million in cash for a mansion in the nation’s capital.
Powell McCormick and Collison officially become directors on April 15, Meta said.
UnitedHealth CEO Andrew Witty testifies before the Senate Finance Committee on Capitol Hill in Washington, May 1, 2024.
Kent Nishimura | Getty Images
Following the massive cyberattack on UnitedHealth Group’s Change Healthcare unit last year, the company launched a temporary funding assistance program to help medical practices with their short-term cash flow needs, offering no-interest loans with no added fees.
A little over a year later, UnitedHealth is aggressively going after borrowers, demanding they “immediately repay” their outstanding balances, according to documents viewed by CNBC and providers who received funding. Some groups have been asked to repay hundreds of thousands of dollars in a matter of days.
Optum, UnitedHealth’s financial, pharmacy and care services arm, is telling borrowers that it reserves the right to “begin offsetting claims payable” to the practices, meaning the company will withhold separate funds until it recoups the loan.
It’s a significant change in posture for the company, which suffered a cyberattack in February 2024 that compromised data from around 190 million Americans, the largest reported health-care breach in U.S. history. The ensuing disruption caused severe fallout across the health-care system, leaving many providers temporarily unable to get paid for their services. Some dipped into their personal savings to keep their practices afloat.
During a Senate hearing about the attack in May, UnitedHealth CEO Andrew Witty said providers would only be required to repay the loans when “they, not me, but they confirm that their cash flow is normalized.”
Several doctors who took advantage of the financing told CNBC that they can’t meet the company’s new demands. Dr. Christine Meyer, an internist who started a practice in Exton, Pennsylvania, received a letter from Optum earlier this month telling her to immediately submit her organization’s payment.
“We are not in any position to start repaying this loan,” Meyer, who started her practice about 20 years ago, told CNBC. She has been a vocal critic of UnitedHealth following the breach.
“I’m just looking at all my legal options at this point,” Meyer said. “But repaying them $750,000 in five days is obviously not going to happen.”
UnitedHealth didn’t comment on specific cases, but a spokesperson for Change Healthcare confirmed that the company has started recouping the loans.
“Now, more than one year post the event and with services restored, we have begun the process of recouping the interest-free funding we provided to providers,” the spokesperson said in a statement.
The company said the U.S. Department of Health and Human Services took the same approach last year “under its own cyber-attack lending program.” HHS launched a separate funding assistance program through the Centers for Medicare & Medicaid Services last March. CMS said it would automatically recoup payments from Medicare claims, and providers could accrue interest, according to a release.
“We continue to work with providers on repayment and other options, and continue to reach out to those providers that have not been responsive to previous calls or email requests for more information,” the Change Healthcare spokesperson said.
Providers were told that UnitedHealth reserved the right to withhold future payments when they signed up for the funding assistance program, the company added. CNBC independently reviewed a copy of a loan agreement for the program and confirmed this statement.
Change Healthcare, which offers payment and revenue cycle management tools, was acquired by Optum in 2022.
After discovering the breach last year, UnitedHealth said it isolated and disconnected the impacted systems. The company paid out more than $9 billion to providers in 2024, and more than $4.5 billion has already been repaid, according to the company’s fourth-quarter earnings report in January. UnitedHealth said providers would receive an invoice once standard payment operations resumed, and that they would be subject to a repayment period of 45 business days.
“Change Healthcare will notify the recipient that the funding amount is due after claims processing or payment processing services have resumed and payments impacted during the service disruption period are processed,” the website says.
Dwindling deposits, lost revenue
While the vast majority of Change Healthcare’s services have been restored over the course of the last year, three products are still listed as “partial service available,” according to UnitedHealth’s cyberattack response website.
And doctors are still reeling.
Meyer said that when the breach took place, she watched her practice’s daily deposits shrivel from the range of $60,000 to $80,000 to about $150 “overnight.” She applied for Optum’s temporary funding assistance program, and after some difficulty and back and forth with the company, she ultimately received a total of $756,900 in financial assistance.
Former Senator Bob Casey Jr., D-Pa., shared Meyer’s story during the congressional hearing in May. He asked Witty about the company’s approach to the repayment process.
“I’d like to absolutely confirm to you and Dr. Meyer that we have no intention of asking for loan repayment until after she determines that her business is back to normal,” Witty told lawmakers. “Even then, we would not look for repayment until 45 business days – 60 calendar days – after that and there would be no interest and no fee associated with that loan.”
“So it would be a determination she makes?” Casey asked.
“That’s absolutely right,” Witty said.
Meyer said that’s not what happened.
UnitedHealth Group Inc. headquarters stands in Minnetonka, Minnesota, U.S.
Mike Bradley | Bloomberg | Getty Images
She received a notice from Optum on Jan. 24, which was viewed by CNBC, that requested repayment since “the service disruption has ended for most clients.” Meyer said she called and told the company she was “not in any position to pay.”
Meyer claims that her practice lost more than $1 million in revenue due to the Change Healthcare cyberattack. She told CNBC the figure was based on a forensic financial analysis her practice carried out by comparing its charges against payments over recent years. The $1.2 million figure accounts for losses across all its insurers, not just UnitedHealthcare, Meyer said.
On April 1, Meyer received another notice requesting immediate repayment within five business days. The letter was addressed to Meyer. But the name of the practice on the letter, Insight Counseling, as well as the total amount due, $925,200, were incorrect.
Meyer said she called Optum again and was told the company made a mistake, but that she had five days to repay her actual total of $750,000. At that point, the company would start withholding her UnitedHealthcare payments, which she described as a “shakedown.”
Meyer said her practice typically receives annual claims payments of about $150,000 to $200,000 from UnitedHealthcare.
“I guess I’ll just let them take those payments back for the next three years until they get their money back,” she told CNBC.
In a post on LinkedIn on Thursday, Meyer wrote that she and her team “made a plan to leave the least amount of money in the account set up to receive payments from UnitedHealthcare. If it isn’t there, they can’t get it.”
‘Very frustrating experience’
Dr. Purvi Parikh, an allergist and immunologist with a private practice in New York, shared a similar story.
Parikh’s practice received about $440,000 in funding assistance after the breach. She said she started getting repayment notices late last year, and that Optum was threatening to offset claims payable to the practice.
“We were already hit very hard by the Change Healthcare hack,” Parikh said in an interview. “Now on top of that, they’re asking for all of this money back or they’re going to hold future payments ransom. It’s just been a very frustrating experience dealing with Optum.”
Parikh’s practice requested a one-month extension on its final payment of $101,650 in January to try and keep UnitedHealth from withholding other payments. In the email request, Parikh’s colleague wrote that “it has been quite difficult to recover financially.”
Optum granted Parikh’s practice the extension.
“People don’t just have that amount of money just sitting around,” Parikh said. “We’ve paid everything back, but it wasn’t without hardship.”
A physician who runs a pediatric practice in New Jersey said UnitedHealth has already started withholding payments from the organization. The practice received more than $500,000 in funding assistance following the Change Healthcare breach.
The doctor, who asked not to be named due to the sensitive nature of the situation, said the practice began receiving phone calls and emails from Optum requesting repayment beginning late last year. The group indicated that it didn’t have the money, but would set up a payment plan and had begun the process.
But the doctor said its billing department noticed that UnitedHealth had already started holding back claims payments. In its explanation of benefits, which details what an insurer will cover, the doctor said the company has a line that reads, “UnitedHealthcare is withholding payment for Optum.”