The Solo-Founder Shift

Sources#

Summary#

Carta's proprietary cap-table dataset on tens of thousands of U.S. companies, published as The State of Solo Founding (December 2025) by Solo Founders with Carta Insights. The measured claim: the share of new U.S. startups on Carta founded by a single person rose from 23.7% in 2019 to 36.3% in H1 2025 — and, in Carta's own Founder Ownership Report 2026 (March 2026), held at about 36% for the full year 2025, up from 31% in 2024. The half-year point was not an artifact.

Read the figures and the framing as two different sources. The numbers are Carta cap-table data — the same instrument class as the platform's other primaries. The publisher is an organization that sells a paid Solo Founders Program on the same page and whose thesis is "Today, solo founding is considered odd. Soon it will be the default." Interpretation throughout is attributed to the publisher; only the figures are carried here. The most useful consequence of reading it this way is that the dataset repeatedly declines to support the framing, which is where the interesting findings are.

The series, and two caveats the report does not make#

Share of U.S. startups on Carta founded by a solo founder (transcribed from the chart image during ingest — the prose gives only the endpoints):

2019	2020	2021	2022	2023	2024	H1 2025	2025 (full year)
23.7%	24.5%	26.0%	27.2%	27.8%	30.5% → 31%	36.3%	~36%

The last column and the 2024 revision come from Carta's own Founder Ownership Report 2026 (March 2026) — see the next section. ~~2024: 30.5%~~ (revised 2026-09-22: Carta's 2026 report states 31% for 2024. The 30.5% is the value transcribed from the 2025 report's chart; both are Carta cap-table figures with Peter Walker on the byline, so read 31% as the publisher's own restatement — rounding, or late-registering 2024 incorporations backfilling the denominator — not as a correction of an error. Keep the 0.5pp gap visible: it is the size of the drift this series carries between publications.)

Two problems with the headline, neither raised in the 2025 source. The first is now settled and the second is not.

~~The final point is a half-year measured against six full years, and it is by far the steepest jump in the series~~ — the concern was right and the projection under it was wrong. (Settled 2026-09-22: the full-year 2025 figure is ~36%, so H1's 36.3% held. The step is still by far the steepest in the series — ~+5pp against +2.7pp for the largest prior full-year move — but it is now a full-year step, not a half-year artifact. The projected "if H1 2025 behaved like any prior year it would read ~32%" is falsified by ~4pp. See the grading in Resolved Questions.)
The denominator is companies on Carta. The series moves with Carta's own customer mix as well as with founder behavior, and neither report addresses platform-composition drift. Solo founders are cheaper and likelier to adopt a free cap-table tier, which would inflate the trend without any change in the underlying population. The full-year datapoint does nothing for this one — a confirmed full-year step is exactly as consistent with a shifting customer mix as a half-year one was.

The rise before 2025 is nonetheless steady and predates ChatGPT (+3.5pp from 2019 to 2022, i.e. most of the pre-2024 movement happened before generative AI was available) — which is itself evidence against the report's AI-first explanation, and is not remarked on. Founder commentary attributes the shift squarely to AI (Daniel Francis: "It's definitely a testament to AI making things much easier"); the pre-2022 slope says falling company-formation costs were already doing the work. Peter Walker (Carta) gives the more defensible version: "This trend reflects technology lowering the cost of company creation."

The full-year datapoint: the jump survived (Carta, March 2026)#

Founder Ownership Report 2026 — Carta's own Data Desk (Peter Walker and Kevin Dowd), published 2026-03-12, empirical. Walker is on both bylines, so this is the same instrument publishing its own follow-up, not an independent replication. What was read is the public landing page: an executive summary plus four highlight bullets, ~1,150 words; the full report sits behind a lead-capture form and was not fetched, so every figure below is prose from the summary and no per-stage table or chart is available to check it against.

The headline claim, verbatim: "About 36% of startups founded on Carta in 2025 were led by solo founders, a jump from 31% in 2024. Over the past 10 years, the proportion of new startups with solo founders has doubled."

The two series are the same series. The denominator phrase is identical — startups founded on Carta — the 2024 anchor matches (31% against the earlier chart's 30.5%), and "doubled over 10 years" implies ~18% in 2015, which extrapolates cleanly off the 23.7% of 2019. So the full-year 2025 reading is ~36% against H1's 36.3%: the steepest step in the series is real at full-year resolution.

How much H2 reversion that leaves is bounded but not measurable. The follow-up gives a rounded figure with no decimal and publishes no H2-only cut, so "about 36%" covers 35.5–36.4%; assuming the two halves are of similar size, H2 2025 lands somewhere around 34.7–36.5% — at worst ~1.6pp below H1, and even the floor sits ~4pp above 2024. The half-size assumption is the weak link (company formation is not uniform across a year, and Carta's cap-table population backfills as late registrations arrive), so treat the band as indicative. The direction is not in doubt; the decimal is simply not recoverable from this page.

Formation is not financing: the funnel the solo trend does not clear#

The follow-up's second highlight is the sharpest thing in it, and it cuts against the headline:

"Among startups that successfully raise venture funding, however, two-person founding teams are most common. Last year, 36% of startups that closed rounds on Carta had two founders, a rate that rises to 40% in the SaaS industry."

Two 36%s that describe opposite ends of a funnel: solo founders are ~36% of companies formed, and two-founder teams are ~36% of companies that close a round. The report does not publish the solo share of round-closers, which is the number that would settle whether the formation trend is propagating into financing at all. What the vault already has is the older, cruder version of the same gap — solo-led companies were 30% of 2024 formations but took 14.7% of priced-round cash (see below) — and this new cut says the composition of the funded population still has a co-founder at its mode. The rise in solo founding is, so far, demonstrated on the formation margin and only weakly on the financing margin.

Founder-to-founder splits are converging#

Among multi-founder teams, equal splits are still the minority but are climbing fast: 27.3% of three-founder teams split evenly in 2025, up from 21%; 16.7% of four-founder teams, up from 10.8%. Both are the largest one-year moves the report reports on any of its series, and they are worth recording here for a reason the source does not draw: Carta clearly can publish distributional facts about how equity is divided, and chooses to publish them for founder-to-founder splits while still publishing only medians for early-employee grants. The employee-equity null below is therefore a choice of cut, not a limit of the dataset.

The dilution arc, and the AI premium#

The follow-up's ownership figures are a stage ladder rather than a solo-vs-team comparison, so they belong to the lifecycle rather than to this page; they are recorded at AI-Native Startup Lifecycle (stage gates) and AI Investment Story, Not Efficiency Story (the AI premium). The headline shape: median founding-team ownership runs ~56% at seed → 36% at Series A, and at Series C the median employee pool (16.8%) overtakes median founder ownership (16.1%) — the founding team stops being the largest single equity block roughly one round after it stops being the majority one. Nothing in this cut is split by founding-team size, so it does not touch the solo-vs-co-founded comparison this page is built on.

The firm-scale twin of the solo-authorship rebound#

The structural parallel with The Solo-Authorship Rebound is close enough to be worth stating as its own finding, because the two sources share an instrument, a period, a proposed mechanism — and a weakness.

	The Solo-Authorship Rebound (Matsui)	This page (Carta)
Unit	a paper	a company
Instrument	left tail of the author-count distribution	left tail of the founder-count distribution
Finding	decades-long decline in solo authorship halts/reverses at end-2022	solo-founded share rises steadily 2019→H1 2025
Mechanism claimed	LLMs substitute for the coauthor's execution work	AI substitutes for the co-founder's execution work
Core weakness	~half the pooled break is venue composition in OpenAlex	trend confounded by platform composition on Carta
Evidence quality	interrupted time series, no untreated unit, heavily stress-tested	descriptive trend, no counterfactual, no robustness work at all

That last row is the asymmetry that matters. Matsui stress-tests his break against composition standardization, history conditioning, cutoff scans, donut specifications and a pandemic-rebound test, and still concedes the causal claim is not identified. Carta's series has none of that apparatus. So this is the weaker of the two measurements by a wide margin, and it is pointed at the more consequential claim. Cite it as a trend that exists, not as an AI effect.

The Solo-Authorship Rebound already recorded Zuckerberg's prediction that firm sizes shrink into "a larger number of companies with fewer people each" as "a prediction where this page has measurement." This page is the firm-scale measurement that comparison was missing — and it partially supports the prediction on company formation while saying nothing about company size, which is what the prediction is actually about.

Where the data contradict the framing#

Three places the dataset declines to support the publisher's thesis. These are the findings worth carrying.

1. Solo founders hire earlier — the organization of one is a waypoint, not a destination#

Median days from incorporation to first hire: 399 for solo founders, 480 for multi-founder companies. The report presents this as a solo-founder virtue ("solo founders tend to hire faster"), and it plainly is a difference. But note what it does to the surrounding narrative: the solo founder's first move is to stop being solo. A co-founded team starts with two people and adds a third at ~16 months; a solo founder starts with one and adds a second at ~13 months. Nobody is running a company of one for long.

This directly qualifies the vault's "one-person company" thread. AI-Native Organization's "organization of one" and Founder as Agent Orchestrator both describe a founder whose leverage comes from agents rather than headcount; Paul Klein IV, quoted in this very report, states the constraint that breaks it — "By default, a solo founder is single-threaded. You must become multi-threaded. You have to have someone building and selling the product while you're hiring." The binding limit is the founder's serial attention, not implementation capacity, and agents do not relieve it. Read against Implementation Abundance Inverts Product Work: implementation got cheap, and the first thing the freed-up founder buys is still a person.

One caveat cutting the other way: both groups are waiting longer to hire than they did a few years ago, which is the trend consistent with AI-substituted execution. The gap between solo and multi is old; the lengthening applies to everyone.

2. Solo founders do not spend their extra equity on talent — the measured null the publisher disputes#

For hires made in 2023–24, median equity grants to the first five employees are near-identical across solo- and multi-founder companies. This is the report's own stated surprise, and it is a real finding: solo founders hold roughly double the founder equity and do not convert any of it into larger early-employee grants.

"There's very little difference in equity grants, which runs counter to the theory that solo founders would be more generous with ownership. We expected equity to be a lever they'd pull to outcompete multi-founder companies for the best talent. Perhaps this is an underused strategy that solo founders could lean on, but largely aren't yet." — Peter Walker, Carta

The publisher then contradicts his own dataset in the same document, which is the sharpest internal disagreement in the source and is recorded here unresolved:

"The Carta data does not align with my experience with solo founders over the last 6 years or the Solo Founders Program in 2025. In both cases, the solo founders I've worked with often gave 2-5x the equity for early employees than the median numbers in the previous chart." — Julian Weisser, CEO of Solo Founders

Both claims can hold without conflict, and the reason is a selection problem the report does not name: Weisser's comparison set is founders who joined an organization that advocates exactly this practice, measured against a platform-wide median. His observation is evidence about his program, not about solo founders. Carta's median is the population fact.

The explanation the report offers for the null is more interesting than the dispute: solo founders "often encounter frameworks built for co-founder teams that have already split the company two or three ways," so they anchor on grant sizes calibrated for a cap table they don't have. Charles Hudson (Precursor Ventures) puts it precisely — "3% is only too much in the context of two founders." If that is right, the null is norm inertia, not preference: a measurable case of advice outliving the structure it was designed for.

3. No efficiency claim is available from this data#

The report's ownership findings are real and clean:

Dilution is near-identical across solo- and multi-founder companies at every early stage in 2024. Walker's reading: "when a solo founder can convince a VC they are a great investment, they don't pay a tax."
Round sizes are near-identical at Series A, slightly lower at Priced Seed and Series B — the seed gap read as a mild team-evaluation bias that fades once there is a business to evaluate.
By Series B, solo founders hold a roughly 50% larger personal stake; median ownership at exit is 75% greater than lead founders in multi-founder companies (2019–H1 2025).
Solo-founded companies took longer to exit in earlier cohorts but exit slightly faster recently.

What none of it is: a measure of output. Carta's dataset contains cap tables, not revenue. So this source characterizes the lean tail's structure — how it is owned, how it is funded, when it hires — and says nothing whatever about its efficiency.

That distinction is load-bearing for AI Investment Story, Not Efficiency Story, whose open question asks specifically about "the deliberately-lean solo-founder tail's RPE." This source does not answer it and cannot. It supplies the population base rate for the tail (the tail is much bigger than assumed — over a third of new companies) without supplying a single revenue-per-head figure for it. The report is careful about the adjacent version of the same trap, and the caveat deserves quoting because it is the most rigorous sentence in the document: "more ownership at exit only implies a better outcome when exit values are comparable, which this data does not capture."

Where the money goes#

Solo-led companies were 30% of startups founded in 2024 but received 14.7% of cash raised in priced equity rounds that year — a ratio the report treats as improving (Miura-Ko: from "around 10% in 2019 to the mid-teens more recently") and frames as investor attitudes thawing.

Walker names the more likely mechanic: the gap "is impacted less by the number of people starting companies as solo founders and more by the number of founders getting through VC filters to raise capital." And cash raised is explicitly a lagging indicator — newer solo cohorts have not reached the later stages where round sizes move aggregates. Both readings predict the ratio closes without any change in investor preference, purely from cohort maturation. Nothing here distinguishes thawing from arithmetic.

Update (Carta, March 2026): a year on, the funded population's modal founding team is still two people (36% of round-closers, 40% in SaaS) — see Formation is not financing above. That is a count, not a cash share, so it is not directly comparable to the 14.7%; but it is the second instrument in a row showing the solo trend far stronger on the formation margin than on the financing one.

Two structural notes:

Solo-founded companies are less likely to raise a pre-seed (SAFE/note) in their first year, and reach their first priced round sooner — in every cohort from 2018–2024. The report suggests they skip the pre-seed stage rather than delay financing; Walker adds that a solo founder's lower burn buys more unfinanced tinkering time.
Sector mix is broadly similar, with solo over-represented in Consumer Products and Services (17.0% vs 12.0%) and under-represented in Pharmaceuticals and Biotech (5.3% vs 8.6%). The biotech gap is the one with an obvious mechanism — deep technical expertise usually has to be paired with commercial experience — and it is the firm-scale echo of the field ordering in The Solo-Authorship Rebound, where laboratory- and instrument-organized disciplines are exactly the ones that show no solo rebound. Two independent datasets, one on papers and one on companies, put wet-lab work in the same position: the execution that AI cannot absorb.

Connections#

The Solo-Authorship Rebound — the same left-tail instrument one unit down, and the better-identified of the pair: solo authorship halting its decline at end-2022, with the same AI-substitution mechanism, the same composition weakness, and far more robustness work. The biotech/wet-lab gap here matches its field ordering exactly
AI Investment Story, Not Efficiency Story — supplies the population base rate for the deliberately-lean tail that page's open question names, and pointedly not its RPE: Carta holds cap tables, not revenue
AI-Native Startup Lifecycle — the staffing dimension from the founding-team side; the lifecycle's headcount bands start at "seed → 10 engineers," and this measures what the team looks like before the first of them arrives
Founder as Agent Orchestrator — the qualification: the orchestrator-founder is real but short-lived on this data, hiring a first employee at a median 399 days. Agents relieve implementation, not the founder's serial attention
AI-Native Organization — the "organization of one" reframed as a waypoint: solo founders are the fastest, not the slowest, to add a second person
Implementation Abundance Inverts Product Work — the economics behind the trend and its limit: implementation got cheap, and the first thing the freed-up founder buys is still a person
Balance-of-Power Superintelligence — the firm-scale prediction this partially tests: Zuckerberg forecasts more companies with fewer people each. Company formation supports him; company size is untouched by this data
The Tragedy of the Cognitive Commons — the apprenticeship reading, weaker here than in the paper case: a co-founder slot that did not form is not obviously a training slot destroyed, since the solo founder hires sooner than the team does
AI and Market Power — founder characteristics measured on a much larger, non-platform population: across 382,108 VC-backed or patenting start-ups in the OECD Start-up Database, having a serial founder is the single largest founder effect in either OECD regression — +4.2 to +5.0pp on the probability of an acquisition exit (base rate 7.58%) and +0.93 to +1.88 log points on lifetime VC raised, against +0.54 for a PhD founder. Carta's series counts how many founders; that one prices which founders, and it does so on the exit and funding margins this page can only describe structurally
Emergent — the celebrated lean-tail exhibit, and the reminder that tail structure is not tail efficiency
Carta — the instrument itself: what the cap-table dataset can and cannot see, the on Carta denominator both reports share, and the two publications this page reconciles

Open Questions#

Is the employee-equity null a real population fact or a median artifact? Carta reports near-identical medians; the publisher claims 2–5× among founders in his own program. A distributional cut — variance or upper decile of first-five grants, split by founding-team size — would settle it, and neither party publishes one. Checked against Carta's own follow-up and still not answered (2026-09-22): Founder Ownership Report 2026 publishes employee equity only as a pool aggregate by stage (12.1% at seed, 16.8% at Series C) and never splits grants by founding-team size. The check did sharpen the question, though: the same report publishes a distribution for founder-to-founder splits (equal-split rates by team size, both rising), so the missing cut is an editorial choice rather than a dataset limit — worth asking the Data Desk for directly rather than waiting for it to appear.
Does the solo-founded tail differ from co-founded companies on revenue per head? This dataset cannot say — it holds cap tables, not revenue — and it is the missing half of AI Investment Story, Not Efficiency Story's tail question. Checked (2026-09-22): Founder Ownership Report 2026 is again cap tables only; it adds ownership-by-stage and sector splits and not a single revenue figure. The gap is structural to the instrument, so no Carta publication will close it — this needs a financials source.
Is the solo share of funded companies rising in step with the solo share of formed companies, or is the trend stalling at the financing gate? Carta publishes solo share of formations (~36% in 2025) and two-founder share of round-closers (36%, 40% SaaS) but not solo share of round-closers — the one number that would say whether the funnel is narrowing on solo teams. Any Carta cut of founding-team size among companies that closed a round, or the gated full report, would settle it.

Resolved Questions#

Does the H1 2025 jump to 36.3% survive a full-year datapoint, or is it a half-year artifact? Every prior step is 0.6–2.7pp and this one is 5.8pp. Trigger: Carta's 2025 full-year or 2026 update to this series. Answered (2026-09-22): the trigger fired — Founder Ownership Report 2026 (Carta Data Desk, 2026-03-12, empirical) reports about 36% of startups founded on Carta in 2025 were solo-led, up from 31% in 2024. Same instrument, same denominator phrase, consistent 2024 anchor and a consistent ten-year doubling. The jump survived: it is a full-year step of roughly +5pp, still by far the steepest in the series. Graded as a prediction, in three parts. Right: the methodological objection — a half-year point is not comparable to six full years, and the anomalous step size warranted a hold rather than a headline — was correct, and the trigger was named precisely enough that a single follow-up publication settled it. Wrong: the substantive prediction underneath it. "If H1 2025 behaved like any prior year it would read ~32%" is falsified by about 4pp; regression toward the historical step size did not happen, and the half-year-artifact hypothesis is dead. Right for the wrong reason: the suspicion that the series is not fixed between publications was vindicated — the 2024 point did move, 30.5% → 31% — but by the publisher's own restatement or rounding, not by the sampling artifact the question hypothesized. Residual, which is a rounding limit and not a reason to keep the question open: the follow-up gives "about 36%" with no decimal and no H2-only cut, so the size of any second-half reversion is unknowable from it (bounded at roughly 34.7–36.5% for H2 under an equal-halves assumption). And the second caveat this page raised — platform-composition drift in the on Carta denominator — is entirely untouched by a full-year datapoint; it is tracked in the body, not as an open question, because no Carta publication can address it.

Sources#

The State of Solo Founding (Solo Founders Report 2025) — The State of Solo Founding (Solo Founders Report 2025), Julian Weisser & Kieran Ryan (Solo Founders) with Peter Walker & Hamza Shad (Carta Insights), 2025-12-09, empirical for the Carta cap-table data on tens of thousands of U.S. companies. COI is direct and disclosed in-file: the publisher sells a paid Solo Founders Program on the same page and its stated thesis is that solo founding is the future — all interpretation above is attributed, and the three sections where the data contradict the framing are the ones carried. Ingested from solofounders.com/report (the ~43K-char full web report) rather than the ~4.6K-char Carta landing-page excerpt; a 100-page PDF behind an email gate was not taken. Chart-parse note: the report is an interactive tabbed document rendering one chart image per tab, and only the share-of-solo-founded-companies chart was captured and transcribed (the annual series in the table above, which the prose gives only as endpoints) — no other chart is cited here, and the raw file records the same restriction. Figures otherwise quoted from prose
Founder Ownership Report 2026 — Founder Ownership Report 2026, Peter Walker & Kevin Dowd (Carta Data Desk), 2026-03-12, empirical for the cap-table figures (rounds raised 2021–2025). Not an independent replication of the 2025 report — Walker is on both bylines and it is the same dataset publishing its own follow-up; treat the full-year confirmation as the instrument restating itself, which is exactly what the open question asked for and no more. Scope caveat: what was ingested is the public landing page (~1,150 words: executive summary plus four highlight bullets). The full report is behind a lead-capture form and was not fetched, so there are no per-stage tables, no charts, and no decimals on the solo-founder figure; every number carried here is from prose. No data visualizations were present on the page to transcribe. The 2024 solo-founder share is restated from 30.5% to 31% relative to the 2025 report's chart — logged as a revision on this page, not an error