Carta's 2026 Founder Ownership Report documents how equity is divided as venture-backed startups progress. Its headline figures are striking: the median founding team retains roughly 56% at seed and 36% at Series A, with digital and AI companies generally retaining more than physical and non-AI companies at comparable stages. The report also tracks team size, equal founder splits, and the point at which employee pools exceed founder ownership. This is valuable descriptive data in a market where private-company terms are usually difficult to observe.
The danger begins when a benchmark starts to feel like an answer. Founder ownership is a percentage, but the economic question is what founders received, built, and risked in exchange for the percentage they surrendered.
Two teams can each own 36% after Series A and be in radically different positions. One may have raised enough capital to reach a defensible milestone on fair terms; another may have accepted a weak valuation, unusual preferences, or too little runway. Fully diluted ownership also does not capture liquidation preferences, participation rights, board control, pro rata rights, debt, vesting, or the probability that the company will ever create distributable value. The same slice of two different pies is not the same outcome.
Stage-based comparisons introduce selection effects. A startup appears in the Series B median only if it survived and chose to raise a Series B on Carta. Companies that grew without another round, shut down, changed cap-table providers, or never used the platform are absent. The report describes its dataset, but the clean progression from seed to later stages can still look like the path of a typical company rather than a series of different selected populations.
Sector differences are equally easy to narrate too quickly. Higher founder retention in AI could reflect investor competition and valuations, as the report suggests. It could also reflect younger company age at a named stage, different capital needs, secondary sales, accelerator terms, or the way sectors and rounds are classified. Physical companies often need inventory, facilities, certification, and working capital that software companies do not. Lower ownership may be the rational price of building a more capital-intensive asset, not weaker founder leverage.
Even the increase in equal co-founder splits is ambiguous. Equality can express trust and shared contribution. It can also avoid a difficult conversation about prior work, future commitment, role, vesting, and what happens when someone leaves. A benchmark showing that equal splits are more common cannot determine whether an equal split is suitable for a particular team. The durability of the agreement matters more than its resemblance to the median.
Founders should therefore use ownership data diagnostically, not normatively. Compare a proposed round with similar companies by sector, geography, capital requirement, and stage definition, but model the whole term sheet and multiple exit outcomes. Ask how much runway the dilution buys, which uncertainty that runway will resolve, what milestone could improve the next financing, and how employee grants will be refreshed. Ownership should be evaluated alongside control, downside terms, tax consequences, and financing alternatives.
The addendum is that dilution is not a score founders should minimize in isolation. Retaining an impressive percentage of a company starved of capital is not success; surrendering more than necessary without buying meaningful progress is not strategy. Carta's medians make a hidden market more legible, but they cannot show whether any individual trade was good. The useful benchmark is not simply how much equity remained. It is how much durable enterprise value, negotiating power, and opportunity the relinquished equity helped create.