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AI Data Payout

Updated October 2026

Karbon data and AI licensing: an accounting practice's work timelines

Independent and sourced. We feature companies that pay us a referral fee. Our scores and reviews don't change for it. How we earn

Karbon's Customer API Terms, updated 2026-05-08, say customers must not use data obtained through the API to train or develop any AI model.1

Two accountants at a shared desk discussing a client email on a laptop while a third flips through a stack of tax forms

Karbon sits where an accounting practice talks. Client email arrives in a shared triage inbox, staff leave notes on a message for a colleague before anyone replies, a work item for a monthly close carries its checklist and comments, and the client request for missing statements sits on the same timeline as the chase emails that followed. For a practice that has run on Karbon through several tax seasons, that timeline is a written record of how accountants gather, question and finish work for clients.

Buyers ask for this shape of data. micro1 names professional services and wants task histories and internal communications; Polyshares buys email from professional services firms. Karbon itself has drawn a firm line in its API terms on AI training.

This page sets out what Karbon holds in writing, what Karbon's own export covers and what it does not, the published lines in Karbon's API and service terms quoted with their dates, and the questions an owner or practice administrator should put to any buyer before data moves.

after termination to ask Karbon in writing for the latest back-up

30 days2

after termination to ask Karbon in writing for the latest back-up

US CPA offices with 10+ employees

6,6313

US CPA offices with 10+ employees

US bookkeeping and other accounting firms with 10+ employees

3,8594

US bookkeeping and other accounting firms with 10+ employees

Karbon tiers with API access: Business and Enterprise

25

Karbon tiers with API access: Business and Enterprise

Worth

What a practice's data may be worth

Pre-set for a typical practice: 25 staff and 8 years of records. No buyer publishes pricing by industry, so industry does not move the band. Our estimate, not a buyer quote.

Buyers

Which buyers want this data

Each reason is the buyer's own published statement about the tools, data or industries it takes, matched to how Karbon accounting practices work.

Featured partners

  1. #1 in our ranking

    7.7 out of 10

    micro1

    Names professional services and financial services, and asks for internal comms, task histories and project management workflows, which is what a Karbon timeline records.10,11

    Typical payout
    $100K to $2M+, micro1 says7

    Watch out for: Says it removes personal details only "when relevant", so ask exactly how.12

  2. #2 in our ranking

    7.4 out of 10

    Polyshares

    Buys email and tickets from professional services firms, but excludes data held on behalf of clients, which in a practice covers most client files.13,14,15

    Typical payout
    $100K to $2M+, Polyshares says8
    Fees
    None, Polyshares says16
    Time to get paid
    An offer in 1 to 2 weeks, then paid in 30 to 60 days17

    Watch out for: Exclusive by default, and every deal it lists is exclusive with no end date.18,19

Everyone else we reviewed

By score, with full reviews. We have no referral agreement with these companies, so we do not link out to them.

  1. #3 in our ranking

    7.1 out of 10

    Mercor

    Lists professional services and finance among its industries and Outlook and Gmail among its tools, the inboxes a practice connects to Karbon.20,21

    Typical payout
    Mercor does not publish a range22
    Fees
    None, Mercor says23
    Time to get paid
    By wire 2 to 4 weeks after signing24

    Watch out for: It confirmed a cyberattack in 2026, and class actions followed.25,26

We feature buyers that pay us a referral fee. Our scores and reviews don't change for it. How we earn. No buyer publishes prices by industry, so within each group the order is the same as in our main ranking.

Buyer demand

How buyers' own tools rate Karbon accounting practices

No buyer publishes a price list by industry. These are settings inside buyers' and brokers' own estimators and intake forms, read from their public pages on 2026-10-14. They show how each company sorts industries, not what any practice was paid. The category shown is the one a practice would most likely pick; that match is ours.

How buyers' tools rate Karbon accounting practices
CompanyIts categoryHow it rates the industry
TroveoBuyerAccounting, tax or bookkeepingTier 1 of 4: "Buyers pay a premium for data from your industry." Price factor 1.3 in its estimator.27
PolysharesBuyerAccounting and taxMarked premium in its intake list28
VMSBrokerAccountingStandard weight in its estimator (factor 1.12)29
VentraBrokerLegal, healthcare, financial services or accountingSays it cannot take these industries right now30

Size rules buyers publish

Checked against 25 staff, the typical practice size this page's calculator is set to. Ask each buyer whether contractors and part-time staff count.

  • PolysharesBuyer

    No headcount rule; the length and texture of the record matter more31

    No floor stated

  • MercorBuyer

    None stated32

    No floor stated

  • TroveoBuyer

    No minimum stated; its estimator starts at 2033

    No floor stated

  • NyneBuyer

    20+ US W-2 employees and 3+ years34

    Clears it at 25 staff

  • Handshake AIBuyer

    20+ full-time employees and 3+ years35

    Clears it at 25 staff

  • micro1Buyer

    30+ employees (its partnership page says 30 to 200)36,37

    Below it at 25 staff

  • PewterBroker

    20+ staff and 3+ years38

    Clears it at 25 staff

  • EndlessBroker

    Roughly 30+ employees39

    Below it at 25 staff

  • VentraBroker

    30+ US employees and 3+ years of records40

    Below it at 25 staff

  • SupersoniqBroker

    50+ employees and 5+ years41

    Below it at 25 staff

What buyers value

What in a practice's records buyers value

The column on the right is not legal advice: it lists what to raise with the buyer before anything is exported.

What in a practice's records buyers value
DataWhere it livesWhy a buyer values itRaise with the buyer
Shared inbox threads with internal notesKarbon triage and shared inboxA client email, the staff discussion about how to answer it, and the reply, kept together.Taxpayer details and attachments inside client emails.
Work item checklists and commentsKarbon work items and tasksThe steps of a close, a return or a payroll run, with comments where something went wrong.Nothing specific
Client requests and follow-upsKarbon client requestsWhat a practice asks clients for, in what words, and how many reminders it takes.Documents clients uploaded against each request.
Activity timelines per clientKarbon contact and work timelinesYears of emails, notes and tasks per client in date order, a long view few systems keep.Nothing specific
Work templatesKarbon work templatesThe practice's written method for each service line, closest to the SOPs and templates micro1 names.Nothing specific
Time and budget entriesKarbon time and budgetHow long each kind of engagement actually took against its budget.Fees and rates attached to named clients.

A week of records

A week of data at a practice

  • Monday: the shared inbox holds overnight client email; a manager notes on one thread that the client's payroll changed and assigns it.
  • Tuesday: client requests go out for bank statements on ten monthly closes, each with a due date.
  • Wednesday: a senior comments on a work item that a reconciliation is off and tags the preparer.
  • Thursday: reminders chase the requests still open, and two clients reply with uploads.
  • Friday: work items move to review, the timeline shows who did what, and next month's work rolls forward from the template.

Process

How it works with each buyer

In each buyer's own published words. Where a buyer publishes nothing, we say so rather than guess.

micro1

What it buys
Internal docs, SOPs and playbooks, knowledge bases, project management workflows, internal comms, templates, CRM and workflow metadata, task histories11
Who qualifies
30 to 200 employees37
Offer range
$100K-$2M+ per data package; over $1M for unique data7
Personal data
PII removed "when relevant"12
Ownership
The company keeps ownership of its data and reviews samples before release42
Time to payment
Not published

Polyshares

What it buys
Slack, email, Drive, CRM, tickets, design files, calls and ERP13
Offer range
$100K-$2M+8
Personal data
A third-party PII partner scrubs data before it is licensed43
Excluded data
Data held on behalf of clients is excluded15
Fees
Charges sellers no fee16
Time to offer and payment
Offer 1-2 weeks after intake; paid Net 30-6017

Mercor

What it buys
Slack, Teams, Gmail, Outlook, Confluence, Salesforce, GitHub, Drive, Notion and 100+ other tools21
Who qualifies
Not published
Offer range
Not published22
Fees
No fees23
Security
SOC 2 Type II44
Time to payment
Wire 2-4 weeks after signing24

Selling or closing

Selling or closing your practice? License its data first

Practices are bought and sold on their client books, and a Karbon account has a short tail when it ends: the service terms give 30 days after termination to ask in writing for the most recent back-up, after which Karbon deletes the data. If a practice sale is coming, settle what is exported, and how, before the subscription closes.2

FAQ

Karbon data: questions, answered

  • Karbon's help center describes an admin export of contact data to a spreadsheet, one row per contact card, and says to contact Karbon Support for further data. We found no official article on exporting emails, notes or tasks in bulk.45

  • Karbon's Customer API Terms, last updated 2026-05-08, say customers must not use data obtained through the API to train, fine-tune or otherwise develop any AI model, machine learning tool, large language model or predictive analytics tool. We quote the clause; we do not interpret it.1

  • Read the API terms with the buyer first. They limit API use to supporting the customer's own accounting firm, restrict API access to Business and Enterprise tiers, and say customers must not resell or license API data or give it to a third party for that party's own commercial benefit.5

  • Karbon's Premium Customer Service Terms, dated 2025-02-13, say in section 8.1 that the customer will own all right, title and interest in all of the Customer Data. Karbon's general Terms of Use say Karbon does not claim ownership of the user's content.46

  • micro1 names professional and financial services and asks for task histories and internal comms. The brokers Endless and Pewter both list accounting. Polyshares excludes data held on behalf of clients, and Nyne names QuickBooks and Xero rather than practice software.10,11,39,38,15,47

  • Buyers do not price them separately. Material the practice wrote for itself, such as work templates and checklists, matches micro1's request for SOPs, playbooks and templates, and keeps client files out, which Polyshares already excludes. Expect a narrower package to be priced as one.11,15

  • Most buyers want 20 to 30 or more: micro1 and Return My Time look for 30+, while Nyne, Cognor Labs and Goldmined.ai start at about 20. Mercor, Troveo and Jottings AI state no minimum. In 2022 there were 6,631 US CPA offices with 10+ employees and 1,383 with 30+, and bookkeeping and other accounting services add 3,859 with 10+.36,48,34,49,50,51,33,52,3,4

  • We do not answer legal questions. Ask the licensing company: their team reviews this with you before anything is signed.

  • We do not answer legal questions. Ask the licensing company: their team reviews this with you before anything is signed.

Before you sign

We do not answer legal questions. Ask the licensing company before you sign: their team reviews these with you.

Questions for this kind of business

  • How will you receive our Karbon data, and does that route fit Karbon's Customer API Terms?
  • How are taxpayer identifiers and client names removed from emails, notes and requests?
  • Would you take only practice-owned templates and checklists if we exclude client files?
  • How do the AICPA Code and IRC 7216 fit into your process for accounting firms?
  • Do customer, vendor or platform contracts, NDAs or API terms restrict this?
  • Do professional rules apply (AICPA, IRC 7216, HIPAA, ABA Model Rule 1.17, insurance agency contracts, adviser rules, state boards)?
  • How is the payment taxed?

Questions for any buyer

  • Is the license exclusive, and for how long?
  • Can you sublicense the data, and to whom?
  • Which AI labs will receive it, and will you tell us?
  • How long do you keep it, and how is it deleted?
  • What is your liability cap, and who indemnifies whom?
  • Will the contract ban re-identification of people in the data?
  • Who removes personal data, by what method, and do we approve it first?

How this page was made

Every figure comes from a published source listed below, each with the date we checked it. Buyer statements are the buyer's own claims and are marked so in the source list. Firm counts come from the US Census Bureau's Statistics of US Businesses. Anything marked as our estimate is ours, not a buyer quote.

Drafted with AI assistance from our research files, then checked against each source. Reviewed 14 Oct 2026. Last updated 14 Oct 2026.

We feature companies that pay us a referral fee. Our scores and reviews don't change for it. See how we earn and how we rank. This site does not give legal, tax or financial advice.

Sources (52)

  1. 1.Karbon Customer API Terms of Use, published 8 May 2026. Accessed 14 Oct 2026. Company's own claim.
  2. 2.Karbon Premium Customer Service Terms, published 13 Feb 2025. Accessed 14 Oct 2026. Company's own claim.
  3. 3.US Census Bureau, Statistics of US Businesses 2022. Accessed 14 Oct 2026.
  4. 4.US Census Bureau, Statistics of US Businesses 2022. Accessed 14 Oct 2026.
  5. 5.Karbon Customer API Terms of Use, published 8 May 2026. Accessed 14 Oct 2026. Company's own claim.
  6. 6.Forbes, published 16 Apr 2026. Accessed 14 Oct 2026.
  7. 7.micro1 company referral page. Accessed 14 Oct 2026. Company's own claim.
  8. 8.Polyshares website. Accessed 14 Oct 2026. Company's own claim.
  9. 9.Bloomberg Law, published 17 Aug 2026. Accessed 14 Oct 2026.
  10. 10.micro1 Enterprise Data Partnership page. Accessed 14 Oct 2026. Company's own claim.
  11. 11.micro1 Enterprise Data Partnership page. Accessed 14 Oct 2026. Company's own claim.
  12. 12.beri.net, published 10 Oct 2026. Accessed 14 Oct 2026.
  13. 13.Polyshares website. Accessed 14 Oct 2026. Company's own claim.
  14. 14.Polyshares website. Accessed 14 Oct 2026. Company's own claim.
  15. 15.Polyshares website. Accessed 14 Oct 2026. Company's own claim.
  16. 16.Polyshares website. Accessed 14 Oct 2026. Company's own claim.
  17. 17.Polyshares website. Accessed 14 Oct 2026. Company's own claim.
  18. 18.Polyshares data handling page. Accessed 14 Oct 2026. Company's own claim.
  19. 19.Polyshares track record page. Accessed 14 Oct 2026. Company's own claim.
  20. 20.Mercor Data page. Accessed 14 Oct 2026. Company's own claim.
  21. 21.Mercor Data page. Accessed 14 Oct 2026. Company's own claim.
  22. 22.Mercor Data page. Accessed 14 Oct 2026. Company's own claim.
  23. 23.Mercor Data page. Accessed 14 Oct 2026. Company's own claim.
  24. 24.Mercor Data page. Accessed 14 Oct 2026. Company's own claim.
  25. 25.TechCrunch, published 31 Mar 2026. Accessed 14 Oct 2026.
  26. 26.HR Dive, published 13 Apr 2026. Accessed 14 Oct 2026.
  27. 27.Troveo business data assessment. Accessed 14 Oct 2026. Company's own claim.
  28. 28.Polyshares intake catalog. Accessed 14 Oct 2026. Company's own claim.
  29. 29.VMS data licensing page. Accessed 14 Oct 2026. Company's own claim.
  30. 30.Ventra partners page. Accessed 14 Oct 2026. Company's own claim.
  31. 31.Polyshares. Accessed 14 Oct 2026. Company's own claim.
  32. 32.Mercor Data. Accessed 14 Oct 2026. Company's own claim.
  33. 33.Troveo business data page. Accessed 14 Oct 2026. Company's own claim.
  34. 34.Nyne sell-company-data page. Accessed 14 Oct 2026. Company's own claim.
  35. 35.Handshake AI data partnerships referral page. Accessed 14 Oct 2026. Company's own claim.
  36. 36.micro1 company referral page. Accessed 14 Oct 2026. Company's own claim.
  37. 37.micro1 Enterprise Data Partnership page. Accessed 14 Oct 2026. Company's own claim.
  38. 38.Pewter website. Accessed 14 Oct 2026. Company's own claim.
  39. 39.Endless website. Accessed 14 Oct 2026. Company's own claim.
  40. 40.Meta Ad Library, Ventra page. Accessed 14 Oct 2026. Company's own claim.
  41. 41.Supersoniq website. Accessed 14 Oct 2026. Company's own claim.
  42. 42.beri.net, published 10 Oct 2026. Accessed 14 Oct 2026.
  43. 43.Polyshares website. Accessed 14 Oct 2026. Company's own claim.
  44. 44.Mercor Data page. Accessed 14 Oct 2026. Company's own claim.
  45. 45.Karbon Help: Export, download and edit contact data. Accessed 14 Oct 2026. Company's own claim.
  46. 46.Karbon Premium Customer Service Terms, published 13 Feb 2025. Accessed 14 Oct 2026. Company's own claim.
  47. 47.Nyne sell-company-data page. Accessed 14 Oct 2026. Company's own claim.
  48. 48.Return My Time Sell My Data page. Accessed 14 Oct 2026. Company's own claim.
  49. 49.Cognor Labs partners page. Accessed 14 Oct 2026. Company's own claim.
  50. 50.Goldmined.ai check page. Accessed 14 Oct 2026. Company's own claim.
  51. 51.Mercor Data page. Accessed 14 Oct 2026. Company's own claim.
  52. 52.Jottings FAQ. Accessed 14 Oct 2026. Company's own claim.