Carve-Out vs Spin-Off vs Split-Off

A conglomerate owns a fast-growing software unit trapped inside a slow-growing industrial company, and the stock market seems to be pricing the whole thing at a discount to what the two pieces would be worth apart. The company agrees the software unit should become its own public stock. There are three different mechanical ways to get there, and they are not interchangeable — one raises cash, one doesn't, and one asks existing shareholders to make a choice.

Carve-out: sell a slice for cash

A carve-out is an IPO of a minority stake in the subsidiary. The parent takes the division public — say 20% of its shares — sells that stake to new investors, and keeps the rest (80%) and, crucially, the cash raised. The parent still consolidates the subsidiary on its own financial statements because it retains control, but the market now has an independent, tradeable price for the piece that was sold. This is the only one of the three structures that brings new cash into the business, which is why it's used when the parent wants to fund debt paydown or reinvestment rather than simply unlock value.

Spin-off: give it away, pro-rata

A spin-off distributes shares of the subsidiary directly to existing parent shareholders, for free, in proportion to what they already own — commonly expressed as a ratio like "1 share of Newco for every 5 shares of Parentco held." No cash changes hands and no new investor enters; the same people who owned the combined company now own two separate stocks in the same proportions they always had. Structured correctly under US tax rules (Section 355 — the parent must give up at least 80% control and there must be a genuine business purpose), a spin-off is tax-free to both the parent and its shareholders, which is the main reason it's the most common route: no capital gains are triggered just for the act of separating.

Split-off: shareholders choose

A split-off also distributes the subsidiary's shares tax-free, but not pro-rata — instead, the parent offers existing shareholders an exchange: trade in some of your Parentco shares for shares of Newco (often at a slight premium to encourage participation, since it's optional). Shareholders who take the exchange end up owning only Newco; those who don't, keep only Parentco. Because participation is voluntary and self-selecting, split-offs also let the parent retire its own stock in the process — every share exchanged away is a share of Parentco taken out of circulation, similar to a buyback.

A worked example

Parentco has 500 million shares outstanding and trades at $40, a $20 billion market cap, of which the market believes its software subsidiary Newco is worth roughly $6 billion. In a spin-off, Parentco distributes Newco shares at a ratio of 1-for-5: a shareholder with 500 Parentco shares receives 100 Newco shares. If Newco starts trading at $60 (implying a $6 billion market cap on 100 million shares issued), that shareholder now holds 500 shares of a smaller Parentco plus 100 shares of Newco worth $6,000 combined — the same total wealth as before, just split into two tickers, with no cash paid.

Compare a carve-out of the same division: Parentco instead sells 20 million new Newco shares (20% of the unit) to IPO investors at $60, raising $1.2 billion in cash that lands on Parentco's balance sheet, not the shareholder's pocket — the shareholder's Parentco stock reflects that cash indirectly, through the parent's now-stronger balance sheet, but no Newco shares land in their account at all.

• Tax status is not automatic. A spin-off only stays tax-free if it clears IRS Section 355 tests (control threshold, business purpose, no pre-arranged resale); poorly structured deals can trigger a large taxable gain for the parent.
• A carve-out is often a prelude to a spin-off, not a final structure — parents sometimes carve out a minority stake first to establish a market price, then spin off the remaining majority stake later, tax-free.
• Split-offs are the least common precisely because they require active shareholder participation; low uptake can leave the parent still holding an awkward residual stake.