Accounting, audit and tax

Accounting is the domain where every structural number goes your way and the one number that matters most goes against you.

A licensed CPA is a genuinely credentialed professional — examined, registered, jurisdiction-tagged, revocable — available at a median of $40.23/hr across 1,595,200 US jobs (BLS, May 2025). That is roughly a third of a physician's marginal-hour cost and half a senior lawyer's. If a buyer pays $90/hr for expert data, the gross margin on a CPA is structurally better than on anyone else in this atlas — see GMV is not revenue before you quote that as profit.

The reachability number is the one nobody else has. 650,667 actively licensed CPAs sit in NASBA's Accountancy Licensee Database as of 27 August 2026, aggregating 53 of 55 jurisdictions (NASBA). No other domain here hands you a queryable national list of verified practitioners in one place. Medicine has dozens of board registers, law has fifty-odd bar registers, design has none. Accounting has one URL.

And there is nobody there. Searching funding news, RL-environment directories and expert-data vendor lists returns no accounting, audit or tax expert-data company selling to AI labs — a [NOTHING FOUND], not a gap in the research.

#What the data actually is

Three products, in increasing order of what they are worth.

Reliability sets. Rivet's TaxBench is the shape of the finding: top models reach pass@1 of 84.2%, 77.2% and 74.5%, which collapse to pass^5 of 42.3%, 27.5% and 22.9% (Rivet). Models get a tax position right once and then fail it under repetition. That is a reliability failure, not a capability failure, and it is the single most sellable observation in this domain because it is exactly what an audit firm cannot tolerate. Data that isolates where the variance lives — phaseouts, credit limits, multi-step document retrieval, the three categories TaxBench tests — is worth more per hour than a bigger pile of correct answers.

Judgement traces on constructed scenarios. A CPA reading reconstructed workpapers and narrating what makes them not tie out. The materiality call. The "this revenue recognition memo is technically defensible and I would still push back" reflex — the narrated-trajectory move, ported to a domain where the reasoning runs longer.

An open audit benchmark. Proof scores 4 on the strength of this alone. There is no public audit benchmark. FinBen, FinQA, TAT-QA and BizFinBench are finance benchmarks, not audit benchmarks (Kili survey). TaxBench itself is held by a private accounting firm, not published as a leaderboard. A rubric-graded reconciliation or audit benchmark built with several hundred licensed CPAs is the cheapest unclaimed marketing weapon in this whole comparison set — the Vals AI play, run in the one vertical Vals does not currently cover.

#Is anyone buying

This is where the page has to stop flattering itself.

xAI named "finance" when it laid off 500 annotators in September 2025 and said it would "immediately surge our Specialist AI tutor team by 10x" across "STEM, finance, medicine, safety" (TechCrunch). But "finance" in lab language means investment banking and equity research — valuation, comps, LBO models. It does not mean audit workpapers, reconciliations or tax positions. Those are different skills held by different people, and the demand evidence points at the banking flavour: see Investment banking and financial modelling, where OpenAI has a named in-house Subject Matter Expert, Investment Banking and xAI ran IB contracts at $45–$100/hr.

Mercor's APEX benchmark covers finance with graders from Goldman Sachs and JPMorgan (TIME). Again: banking. Vals AI benchmarks banking and reports frontier models completing fewer than 52% of real financial analysis tasks, and retired its CorpFin benchmark in May 2026 because it "stopped producing meaningful differentiation" (AI Business Weekly).

The buyer you can name is one tier down. Fieldguide raised a $75M Series C led by Goldman Sachs for agentic audit and advisory and announced an audit-agent co-build with Aprio in August 2026 (Fortune, Inside Public Accounting). Basis raised $100M for accounting agents (CPA Practice Advisor). Rogo raised a $160M Series D for finance agents (PR Newswire). Each needs audit and tax evals. None has a data supplier. Real money — but not the frontier-lab buyer pool: application companies buy in the hundreds of thousands, labs in the tens of millions.

Budget scores 2. An argument that a buyer should spend is a 2, not a 4, and this is the archetype.

#Getting the experts

Reach scores 5 and it is earned by a URL. NASBA's ALD plus the state board licence-verification registers give you every CPA by jurisdiction and status. Layer on: 50 state CPA societies, each with a member directory and CPE calendar; CPE providers Becker, Surgent and CPA Academy, whose rosters are the continuing-education-motivated segment — and CPE credit is itself a currency you could pay in, which no other domain offers; Going Concern and CPA Trendlines; r/Accounting and r/CPA, unusually candid about compensation; and Inside Public Accounting's firm rankings for targeting ex-Big-Four staff.

The seasonality is a feature. CPAs have a pronounced trough from May to December when marginal-hour supply is cheap and abundant. Nobody else in this atlas gets a predictable annual half-year of slack capacity — see Building the supply side.

#What it costs to run

Cost scores 5. No rigs, no licences you must buy, no building. The inputs are public filings — 10-K, 10-Q, XBRL — published IRS guidance, PCAOB inspection reports and constructed fact patterns. The variable cost is CPA hours against a $40.23/hr floor. Assume you must pay 1.5–2x the day rate to buy an evening hour and you are still under $85/hr, comfortably inside the band Mercor clears at across all domains.

The reason this matters is What a rake can actually be. On a $150/hr sell price, a $70/hr cost of expert leaves a spread that survives a customer negotiating you down twice. On a physician at $215/hr it does not — see Clinical medicine.

#Who is already there

Nobody in the data-supply position. Rivet is an AI-enabled accounting firm staffed by 40+ former Big Four accountants whose TaxBench tasks came from real client workflows on its own platform, validated by those 40+ accountants (Rivet). It is a firm that built an artefact, not a vendor selling one. Halluminate and AfterQuery touch the adjacent finance-environment space (rl-list) — see Halluminate.

Room scores 5, the only 5 in this set alongside Sales and GTM, and unlike sales it comes with a buyer you can name.

#What would kill it

Audit workpapers belong to the firm and are subject to PCAOB inspection and retention rules — an auditor cannot export them. AICPA confidentiality and independence rules constrain what a practising CPA may say about clients. All of it is survivable by never touching a client file: pay CPAs for judgement about constructed scenarios only. Rivet proves the construction works.

Defense scores 3. The supply is cheap, which is good for margin and bad for exclusivity. What keeps it defensible is that the tax code and the audit standards change every year, so the data needs refreshing on a legislated schedule — a recurring-revenue shape most niches have to argue for.

#The first ninety days here

Pull the NASBA register and the state board lookups; build a verified list. Recruit 40–60 CPAs off r/Accounting, Going Concern and two state society CPE calendars, targeting ex-Big-Four seniors in the May-to-December trough. Pay $75–90/hr, no client data, ever, in writing on the first screen.

Then build the benchmark before you build the dataset. Two hundred rubric-graded audit and reconciliation scenarios from public filings, scored by three CPAs each, published with a leaderboard. Report pass^k, not pass@1 — TaxBench already showed that is where the story is, and repeating the finding in audit is a headline Fieldguide's product team cannot ignore. See The first ninety days for the general form and The specialist wedge for why the benchmark is the sales motion, not the marketing.

#Where the record is thin

No observed clearing price exists for accounting AI-data work specifically. Mercor publishes rates for lawyers and civil engineers; it publishes none for CPAs. The $75–90/hr figure above is an inference from the general expert band, not an observation.

TaxBench's numbers come from Rivet's own site and have not been independently reproduced. The [NOTHING FOUND] on competitors is a negative from directories that are SEO properties rather than registries — good for name discovery, unreliable for coverage. And the demand case rests on reading "finance" narrowly; if a lab means audit when it says finance, budget here is a point too low.