Public companies are buying a lot of cryptocurrency all of a sudden.

Why it matters: The trend often blends meme-stock hype with inventive financial engineering, all aimed at beating the market in a booming sector. For some, it also carries a potentially explosive risk if crypto markets turn south.

The big picture: More than 100 public companies have bought bitcoin alone to park in their treasuries. For some, it's just a small fraction of their assets. But for a few, buying crypto has become their main business strategy.

Between the lines: The argument for buying stock in a "crypto treasury" company — as opposed to buying the actual crypto — is they can grow the value of their shares at a faster rate than the price of the crypto they target.

• The secret lies in some old-fashioned financial wizardry, crafted to fuel relentless crypto accumulation without heavily diluting shareholders.
• Successful execution results in a stock trading at a premium to the value of its underlying crypto holdings.

Reality check: This is also what can make these companies risky for investors.

• Some of these companies raise money by issuing low-cost convertible bonds and preferred shares, which are used to buy more cryptocurrency. As long as the firm's share price keeps rising, the system rolls on and on.
• But buying crypto on leverage creates complex strategies that become highly dependent on crypto prices continuing to rise.

Zoom out: The godfather of this crypto strategy is Strategy, formerly known as MicroStrategy, which has been buying bitcoin aggressively since summer 2020 to great success.

• Its founder, Michael Saylor, has become possibly the most prominent bitcoin evangelist in the world.

Zoom in: The company today has many imitators, and the trend now extends well beyond bitcoin.

• Earlier this month, investors poured $425 million into SharpLink, an e-sports marketing company, which intends to use the cash to buy ether. SharpLink stock promptly doubled in value, even though the token of the second-largest blockchain in the world has been moribund for years now.
• Other companies have unveiled plans to buy assets like Solana and Tron.

Threat level: In the 15 years since the first block of bitcoin, digital assets have been prone to periods of severe and highly mutually correlated downturns in prices.

• Strategy has been getting more and more complicated in its offerings, issuing convertible bonds and three new preferred stock instruments: Strike, Strife and Stride, which each offer different levels of risk and yield.

What to watch: If one of these bets fails to work out (Strategy itself has no notes that mature for the next several years), that could force the company to sell its crypto holdings in order to meet its obligations.

• And this could spark downturns in other cryptos or force other companies to sell. If lots of companies with large holdings of digital assets sell at once, the cycle would accelerate.

Health insurers are starting to notify states that tariffs will drive up the premiums they plan to charge individual and small group market enrollees next year.

Why it matters: The Trump administration's trade policy is adding another layer of uncertainty for health costs as Congress considers Medicaid cuts and is expected to sunset enhanced subsidies for Affordable Care Act coverage.

• "There are sort of a perfect storm of factors that are driving prices up," said Sabrina Corlette, a research professor at Georgetown's Center on Health Insurance Reforms.

The big picture: Health insurers calculate monthly premiums in advance of each year based on the expected price of goods and services and projected demand for them.

• Tariffs unveiled by President Trump are expected to drive up the cost of prescription drugs, medical devices, and other medical products and services. Some of the difference ultimately would be passed down to enrollees.

Where it stands: A handful of health insurers administering individual and small group plans have already explicitly told state regulators that tariffs are forcing plans to raise enrollee premiums more than they otherwise would next year, KFF policy analyst Matt McGough wrote in an analysis out Monday.

Insurers "don't have any historical precedent or data to project what this is going to mean for their business and health costs," McGough told Axios. "I think it really makes sense that they're trying to hedge their bets."

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It's mango season in Miami, and that marks the return of the unusual tradition of fruit barter. Axios Miami's Sommer Brugal and Martin Vassolo are here to explain.

Anyone with a mango tree knows the three stages of mango season:

1. Hoarding: After waiting all year, you cherish every single mango you get as if it were the last one on earth.

2. Heaven: It's raining mangoes. Every time you step outside, there's at least a couple of mangoes under your tree, like golden goose eggs.

3. Help!!!: No matter how many you eat or freeze, you've still got exactly 30 mangoes on your counter at all times.

Why it matters: Mangoes — Miami's most popular fruit — are practically legal currency this time of year, and there are several local shops that will trade you mangoes for bread, ice cream and other goods.

Zoom out: As Miami New Times reported, there's a list of shops around the city that'll swap mangoes, in varying ratios, for ice cream, bread, even chicken wings.

💭 Martin's thought bubble: Admittedly, when I first heard of the mango barter market, I scoffed. "My mangoes are too valuable to give them up."

• Then I hit Stage 3 of mango mania.

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