Why companies spend a trillion dollars erasing their own shares.

In 2024, the five hundred biggest public companies in America spent a record $942 billion buying their own shares back. That is more than the combined annual defence budgets of Germany, France and the United Kingdom, routed through stock exchanges so that the firms could end the year owning slightly fewer of themselves. Apple alone spent more than $104 billion — its largest annual buyback ever, on top of every other buyback it had ever done.

To anyone outside finance, the exercise sounds paradoxical. A company earns money. Rather than building a factory, hiring engineers, paying down debt, or simply handing the cash to its shareholders, it goes into the open market and uses that cash to remove its own stock from circulation. The shares it buys are usually cancelled. The cash is gone. The company ends the day smaller than it started.

Once you understand what is actually happening in that transaction — what the cash is buying, what the shareholders are receiving, and what the math does to the per-share numbers reported the next quarter — almost everything else about modern corporate finance becomes easier to read.

01 The mechanics

A stock buyback, or share repurchase, is mechanically the simplest transaction a public company can do. The company goes into the stock market and buys its own shares — exactly as you or I might buy them — through a broker, at whatever price they happen to be trading at that day. The shares it acquires are then either cancelled outright or held by the company itself as “treasury stock” and effectively retired from the float.

Two things change as a result. The first is obvious: the company has less cash than it did before, because it spent that cash on its own equity. The second is what makes the exercise interesting: the company has fewer shares outstanding, which means every remaining shareholder now owns a slightly larger slice of it.

That is the whole transaction. There is no transfer of ownership to a new party, no debt being created, no asset changing hands. The company has shrunk both sides of its balance sheet at once — fewer dollars on the asset side, fewer claims on the equity side — and concentrated its remaining ownership among the shareholders who chose not to sell.

02 The math CFOs love

The most quoted reason for buybacks is that they “boost earnings per share”. That phrase sounds suspicious — as though the company were cooking the numbers — but the mechanics are just arithmetic.

EPS is one fraction: net income on top, share count on the bottom. A company that earned $1 billion against 1 billion shares outstanding reports $1.00 in EPS. If the same company spends $100 million repurchasing 10 million of those shares the following year, and earns the same $1 billion, its new EPS is $1 billion divided by 990 million shares — or $1.0101. It has not made a single dollar more in profit. But the per-share number every analyst quotes has risen by about 1 percent.

For a chief financial officer whose pay packet, and whose chief executive’s pay packet, is tied to EPS growth, that is not a rounding error. It is an outright outperformance. Multiplied across hundreds of large companies and a decade of consistent buying, the effect on the headline numbers of the US market is enormous.

03 Buybacks vs dividends

The other obvious way to return cash to shareholders is to pay it directly, as a dividend. From an economic-textbook perspective, the two should be near equivalent: the company hands over cash, the shareholder receives cash, and the company’s per-share value adjusts to reflect what it just gave up.

In practice, three differences matter.

The first is tax. When a US company pays a dividend, that dividend is taxed in the shareholder’s hands in the year it is paid, every year, often at a different rate than capital gains. When a company buys back stock, no shareholder receives anything unless they actually choose to sell their own shares — and only those who sell pay tax, at capital-gains rates, on their own timing. For long-term holders who never sell, the gain is, in effect, deferred indefinitely.

The second is signalling. A dividend is a standing commitment — once raised, the market punishes any cut as a sign of trouble. A buyback is a one-off purchase. It can be quietly scaled up in good quarters and quietly paused in bad ones without the same reputational damage. That flexibility is precisely why companies with volatile earnings prefer it.

The third is concentration. Dividends go out evenly to every shareholder in proportion to their stake. Buybacks concentrate ownership in the shareholders who do not sell — which is often, in practice, executives sitting on options and long-term institutional holders.

04 How the habit got built

Before the 1980s, open-market buybacks were rare, mostly because the law treated them as a close cousin of market manipulation. The Securities Exchange Act of 1934, written in the immediate aftermath of the 1929 crash, was designed precisely to stop companies and insiders from influencing the price of their own stock. A company buying its own shares on the open market looked, to a regulator of that generation, suspiciously like the practice the Act was meant to prevent.

That changed on 17 November 1982, when the SEC adopted Rule 10b-18 — a voluntary “safe harbour” that protected companies from manipulation charges as long as they followed certain limits on timing, volume, price and broker. The rule did not legalise buybacks outright; it simply removed the legal risk that had been keeping them small.

It was enough. In 1980, US corporations spent roughly $6.6 billion repurchasing their own shares for the whole year. By 2024, that figure had grown nearly 150-fold, to $942.5 billion. The first quarter of 2025 set a single-quarter record at $293.5 billion, with Apple again topping the league table. Over the four decades since Rule 10b-18, buybacks have grown from a footnote in corporate finance to the single largest source of returned cash on the American stock market — exceeding dividends in most years.

05 The criticism

For a tool that started as an administrative tidy-up, buybacks have collected an extraordinary range of critics — from union leaders to senators to former Federal Reserve chairs. The substance of the complaint usually reduces to three claims.

The first is about who benefits. Because buybacks lift the share price and, with it, the value of executive stock options, they disproportionately enrich the shareholders and executives whose pay is tied to share performance. The top 10 percent of American households owns more than 90 percent of corporate equity; the bottom half owns about 1 percent.

The second is about what the cash was not spent on. Every dollar a company uses to buy its own stock is a dollar it did not invest in a new product, a higher wage, a research lab, or a debt reduction. Critics argue that the sheer scale of repurchases over the last decade is evidence of corporate America preferring financial engineering to actual building.

The third is about short-termism. Because buybacks can mechanically lift EPS in the same quarter they are executed, they offer an unusually quick way to hit a per-share target — one that does not require any real growth in the underlying business.

There are credible counter-arguments to each. Money returned to shareholders does not vanish; it is recycled into other investments. Companies without obvious projects to fund are arguably right to return cash rather than hoard it. And in industries with volatile demand, the flexibility buybacks offer is a feature, not a bug. But the criticism has stuck — and in 2022 it produced an actual law.

05 The tax that changed the math

In August 2022, as part of the Inflation Reduction Act, Congress imposed a 1 percent federal excise tax on net buybacks by US public companies, effective from 1 January 2023. The tax is small — by S&P Dow Jones’s estimate, it clipped roughly 0.4 percent off S&P 500 operating earnings in 2024 — but it was the first time in US history that buybacks were treated by the tax code as a distinct, taxable event rather than simply a kind of share trade.

Several proposals in 2024 and 2025 floated raising the rate to 4 percent. Whether any of them pass, the harder principle — that buybacks deserve their own line in the tax code — is now established. A future Congress that wants to tilt the math against repurchases has the lever already cut.

For now, the trillion-dollar habit continues. Companies buy themselves back. Share counts quietly fall. EPS quietly rises. Executives are paid against per-share targets they helped to design. And the gap between the headline number on a press release and what actually happened inside the business widens by a small, mechanical amount every quarter. Knowing exactly what is happening in that transaction — and what each side gives up — is half the work of reading a modern corporate balance sheet.

This article is an educational breakdown for TheSpreadline and is not investment advice. Figures reflect publicly reported terms at the time of the deal.