How AI labs source domain experts

Four ways to source domain experts

AI labs, vertical-AI builders and evaluation vendors need professionals who can judge a model’s work in their own field. There are four main ways to find them.

Expert marketplaces and platforms

The first route is a platform that screens professionals at volume and pays by the hour or per task. Mercor’s experts page shows “516k” roles created and “$4M+” in daily payouts (read October 11, 2026). Its CEO, Brendan Foody, said on X that its annualized revenue run rate “has crossed $2 billion” (TechCrunch, July 9, 2026). AfterQuery says it has “nearly 100,000 verified practicing professionals” and has “surpassed $100 million in annual revenue run rate” (Business Wire, April 9, 2026).

Screening differs by platform. micro1 vets through “AI Interviews”. Mercor’s legal network uses “a short AI interview, about 20 minutes total”, then checks license and background.

Eligibility differs too. Handshake’s AI fellows “must be based in the U.S.”, and Turing Frontier, announced April 9, 2026, is for “Verified U.S.-Based Experts”.

Managed expert teams

A managed team delivers the work as a unit, with someone accountable for quality. Axiom says it has deployed “100+ attorneys” on training and evaluation for a legal-AI product, in “Teams of 5–15 lawyers by practice area” (read October 11, 2026). Snorkel AI calls its Expert Data-as-a-Service “a white-glove solution” (Business Wire, May 29, 2025).

Expert networks

Expert networks are moving into the same work. Ethos, a London expert network, raised a “$22.75 million Series A” led by a16z and counts “leading foundational AI labs” among its customers (TechCrunch, May 6, 2026). A GLG job ad, copied on Built In and removed on May 19, 2026, described GLG selling “human-in-the-loop (HITL) data” to “foundation model providers”.

Direct hiring

The fourth route is to engage professionals directly. The lab controls who sees its data, and its own team finds the people, checks qualifications and conflicts, and applies each profession’s conduct rules. None of the sources we read measures how many labs work this way.

What platforms publish on pay

The table shows nine listings as we read them on October 11, 2026, with hourly pay copied exactly as each platform gives it. These are each platform’s figures, not what Kernavique pays or charges.

Mercor’s “Clinicians” listing is a US role for nurse practitioners. Of the listings that named the UK on platforms’ own pages, only Alignerr’s Finance & Accounting Task Author and Mercor’s Private Equity Associate were open when we read them. Our domain experts role page sets these listings out by profession.

What to check before engaging UK professionals

This section summarizes regulator guidance we read on October 11, 2026. It is not legal advice, and a borderline case should go to the regulator’s ethics helpline.

Solicitors

• The work. Writing rubrics, reference answers or grades is not among the reserved legal activities, such as the conduct of litigation, that need a practising certificate (SRA, updated November 25, 2019).
• Who engages them. Under section 1A of the Solicitors Act 1974, a solicitor employed in connection with legal services by a solicitor, a law firm or another authorized provider is “deemed to be practising as a solicitor” and needs a certificate. That can catch a legal-AI business that is itself an authorized firm.
• The title. Without a certificate, a solicitor should not be described as a “solicitor” unless it is clear they are not qualified to act as one. Check bios and team sheets.
• Client matters. Paragraph 6.3 of the SRA Code of Conduct requires solicitors to keep clients’ affairs confidential “irrespective of your role”.

Barristers

• A practising certificate is needed to hold out as a barrister “in connection with the supply of legal services” or to carry on reserved legal activities (BSB, updated March 3, 2026). An unregistered barrister can do rubric work but must not hold out in that way.
• The BSB Handbook (version 5.0, in force June 15, 2026) applies to unregistered barristers, and Core Duty 5, on not diminishing “the trust and confidence” the public places in the profession, applies at all times.
• If an unregistered barrister supplies legal services to an “inexperienced client”, rule rC144 requires them first to explain, among other things, that they are “not acting as a barrister”, and to get written confirmation.

Chartered accountants and tax specialists

• ICAEW calls its definition of accountancy services “wide ranging” and says roles that draw on chartered-accountant skills “are likely to fall within the definition” (March 4, 2020). UK tax grading work may fall inside it.
• The test is then the relationship. No practising certificate is needed where the member is “not in a client/principal relationship”, the organization accepts responsibility for the work, and the member is not held out as a principal.
• If the engaging vendor is an accounting firm, ICAEW’s subcontractor helpsheet (February 11, 2025) says a certificate is “likely” needed where a specialist service passes to the firm’s client.

Doctors

• The GMC says Good medical practice and its guidance apply “to the extent that they’re relevant to an individual’s practice”, so non-clinical evaluation work is covered.
• The GMC asks doctors to be open about their interests with their employer or contracting body. NHS England says staff should declare outside work and may need prior approval (September 17, 2024), though its guidance does not cover GP practices or private providers.
• The GMC says removing names, ages or addresses is unlikely to be enough to anonymize patient data, and asks for controls that minimize the risk of re-identification.

Designing the program

Settle four things before anyone starts.

• Vetting. Confirm each qualification with the regulator, not only a resume. Mercor’s General Physician listing checks “license status, residency completion, and current practice setting”. For UK professionals, also check practising certificates and titles.
• Conflicts. Check each expert against the clients, employers and products in the domain you are testing. A conflict can arise if the AI vendor sells into a doctor’s own trust.
• Calibration. Agree what a good answer is before grading starts. One Mercor UK listing describes recording “what a top performer in your own profession would actually have delivered”. Have experts grade a sample independently, then fix the rubric where they disagree, as our Evaluation Panels do.
• Confidentiality. Build tasks from public law or synthetic facts. Mercor’s standard listing term says the work “will not involve access to confidential or proprietary information from any employer, client, or institution”.

In practice

Match the route to the work: a platform for breadth, a managed team for sustained work under one lead, a network for specialist judgment, direct hiring for full control. Write the UK checks into the brief, or see Expert Program Design to set the structure first. If you source experts with Kernavique, we agree the shortlist timing with you at the brief call, based on the role and the market.

What we left out

• Pay seen only on aggregator copies or in search snippets, including several UK legal listings.
• Pay for compliance and financial-crime experts. No listing we found names UK eligibility.
• micro1’s revenue. Its own page and a press report give different figures.
• The BSB’s definition of “legal services” and ICAEW’s list of accountancy services. Both sit in documents we did not open.
• Other bodies’ rules, including ACCA, CIOT, CILEx Regulation, the Law Society and the FCA.