Short answer. 2025 reordered the industry. Meta paid $14.3bn for 49% of Scale AI in June and hired its founder; within days Google — Scale's largest customer at roughly $200m of planned 2025 spend — OpenAI and Microsoft began moving work elsewhere, and bootstrapped Surge AI, already out-earning Scale at $1.2bn of 2024 revenue, inherited the frontier-lab crown. LXT closed its Clickworker acquisition and emerged with 7m+ contributors across 1,000+ language locales. The ten that defined the year: Appen, TELUS Digital, Surge AI, Scale AI, LXT, iMerit, Defined.ai, Sama, Nexdata and Shaip.
No year in the short history of the AI training data industry was as dramatic as 2025. In June, Meta paid $14.3 billion for a 49% stake in Scale AI — the industry's most valuable company, then valued at $29 billion — and hired its founder Alexandr Wang to run Meta's new superintelligence lab. Within days, Google (Scale's largest customer at roughly $200 million in planned 2025 spend), OpenAI, Microsoft, and xAI began cutting ties. One word drove every defection: neutrality. Frontier labs would not route their proprietary training data through a company part-owned by a direct rival.
That single event reordered the entire market. Bootstrapped Surge AI — which had quietly out-earned Scale with $1.2 billion in 2024 revenue — inherited the frontier-lab crown. LXT completed its Clickworker acquisition in January 2025 and finished full platform integration by July, emerging with 7 million+ contributors across 1,000+ language locales. TELUS took TELUS Digital fully private in October 2025. And across the industry, demand shifted decisively from cheap microtask crowds toward expert-grade, multilingual human data for LLM training, safety, and evaluation.
Against that turbulent backdrop, here are the ten companies that defined global multilingual AI data collection in 2025 — ranked on language coverage, crowd scale, service depth, enterprise credibility, and recognition across independent 2025 industry analyses.
How we ranked these companies
Language & locale coverage in 2025 — documented language and dialect reach during that calendar year.
Global crowd & workforce scale — size and geographic spread of the contributor network as reported in 2025.
Service depth — custom collection, off-the-shelf datasets, annotation, RLHF/LLM alignment, and evaluation.
Enterprise credibility — certifications, compliance, analyst recognition, and marquee clients through 2025.
Independent recognition — consistent placement in reputable 2025 industry rankings and retrospective analyses.
The Top 10 of 2025
1. Appen
The multilingual veteran steadying the ship Headquarters: Sydney, Australia (founded 1996)
Language coverage (2025): 235+ languages (expanding toward 500+ locales) via 1M+ contributors Best for: Massive multilingual speech and text collection, RLHF, LLM data programs Appen entered 2025 leaner after losing Google in 2024, but its core asset remained untouchable: a vetted crowd of over 1 million contributors spanning 170+ countries and the deepest documented language coverage in the industry. Through 2025 the company pushed hard into generative AI — RLHF, supervised fine-tuning demonstrations, and multilingual LLM evaluation — while continuing landmark collection programs for code-switched speech, regional dialects, and low-resource languages. When frontier labs fled Scale AI mid-year in search of neutral vendors, Appen's independence and 25+ years of multilingual infrastructure made it a natural beneficiary.
Key strengths in 2025:
Deepest multilingual bench: 235+ languages with dialect, code-switching, and low-resource capability, expanding toward 500+ locales.
Mega-crowd: 1M+ vetted contributors across 170+ countries.
Neutrality dividend: an independent vendor at the exact moment neutrality became the industry's most valuable currency.
GenAI services: maturing RLHF, instruction data, and multilingual evaluation programs.
Verdict: Still the reference point for planet-scale multilingual data in 2025 — and newly attractive as a neutral partner.
2. TELUS Digital (AI Data Solutions)
Enterprise multilingual leadership through a year of transformation Headquarters: Vancouver, Canada Language coverage (2025): 500+ languages and dialects; AI Community of 1M+ contributors Best for: Audited enterprise programs, multilingual NLP, multimodal data 2025 was transformational for TELUS Digital. The company completed its rebrand from TELUS International, absorbed the loss of Meta's content-moderation contract in April (affecting roughly 2,000 Barcelona-based employees), and in October 2025 was taken fully private by parent TELUS Corporation, delisting from the NYSE and TSX. Through it all, its AI Data Solutions arm kept delivering what few others could: a managed AI Community of over 1 million annotators and linguists working across 500+ languages and dialects on a proprietary platform, with the SOC 2, ISO 27001, and GDPR compliance posture that regulated enterprises demand.
Key strengths in 2025:
500+ languages and dialects: across text, image, audio, video, and geo data on one platform.
Enterprise governance: Everest Group PEAK Matrix Leader heritage, deep compliance certifications.
Expert workforce: tens of thousands of advanced-degree contributors for domain-heavy work.
Strategic stability: full TELUS ownership from October 2025, ending public-market pressure.
Verdict: The 2025 enterprise standard for multilingual programs that had to survive an audit — even amid its own reinvention.
3. Surge AI
2025's breakout: the bootstrapped giant that took the frontier crown Headquarters: San Francisco, USA (founded 2020)
Language coverage (2025): Multilingual expert cohorts across major world languages, ~50,000 vetted contractors Best for: Premium RLHF, multilingual safety and red-teaming, frontier LLM data Long mislabeled a boutique, Surge AI was revealed in 2025 as the industry's quiet giant: it had booked $1.2 billion in 2024 revenue — more than Scale AI's roughly $870 million — while entirely bootstrapped. When Meta's stake broke Scale's neutrality in June 2025, Surge inherited the frontier-lab human-feedback crown, counting Google, Meta, Microsoft, Anthropic, and Mistral among its customers, and spent the year in talks for a first outside round at a reported $25–30 billion valuation. Its vetted expert-contractor model — roughly 50,000 high-skill workers handling preference ranking, reasoning evaluation, and multilingual safety probes — defined the industry's new premium tier.
Key strengths in 2025:
Frontier-lab dominance: the neutral premium vendor of choice after the Scale–Meta deal.
Elite multilingual cohorts: senior annotators for high-skill subjective labeling and East Asian and European language safety work.
Extraordinary economics: $1B+ revenue, profitable since launch, no outside capital until 2025.
Quality-first model: vetted experts over anonymous crowds — the template the whole industry began copying.
Verdict: The defining company of 2025: proof that expert-grade multilingual data, not crowd size, is where the value moved.
4. Scale AI
From industry king to cautionary tale — in one week Headquarters: San Francisco, USA (founded 2016)
Language coverage (2025): Multilingual RLHF via ~240,000 global contractors Best for: Industrial-scale RLHF, evaluation, and government AI programs Scale AI began 2025 as the undisputed market leader and ended it as the industry's biggest cautionary tale about neutrality. Meta's $14.3 billion investment for a 49% stake in June valued Scale at $29 billion — and immediately triggered an exodus: Google, OpenAI, Microsoft, and xAI cut or wound down contracts within days, and Scale laid off about 14% of staff (200 employees) in August while discontinuing work with 500 contractors. Yet Scale remained a formidable business, with revenue just under $1 billion, Meta committed to paying at least $450 million a year for five years, government-grade security credentials, and industrial multilingual RLHF tooling that few could match.
Key strengths in 2025:
Still-massive capability: industrial RLHF and evaluation pipelines across dozens of languages.
Government franchise: FedRAMP-grade security keeping public-sector AI work intact.
Guaranteed backbone: Meta's five-year, $450M+/year commitment underwriting operations.
The neutrality lesson: 2025's proof that in AI data, trust is the product.
Verdict: Wounded but far from finished — 2025's most dramatic fall was still one of its largest businesses.
5. LXT
The consolidation completed: 1,000+ locales, 7 million contributors Headquarters: Toronto/Mississauga, Canada (founded 2010)
Language coverage (2025): 1,000+ language locales across 150+ countries Best for: Massive multilingual collection at speed, managed + self-service delivery LXT's Clickworker acquisition — announced December 2024 — closed on 22 January 2025, and full platform integration was completed on 31 July 2025. The result transformed LXT from a respected 45-language mid-tier provider into one of the most linguistically expansive vendors on Earth: a unified platform spanning 150+ countries, 1,000+ language locales, and 7 million+ contributors, combining managed AI data services with self-service crowd access. Backed by ISO 27001, GDPR, HIPAA, and PCI-DSS compliance, LXT ended 2025 as the industry's best answer to 'we need fifty thousand recordings in ten languages by Friday.' Key strengths in 2025:
Extreme locale coverage: 1,000+ language locales — the widest documented in the industry post-integration.
7M+ contributor crowd: instant scaling for massive multilingual collection projects.
Dual delivery model: fully managed programs plus self-service platform, unified mid-2025.
Strong compliance stack: ISO 27001, GDPR, HIPAA, and PCI-DSS certified.
Verdict: 2025's best value for sheer multilingual breadth and speed — the year its big bet paid off.
6. iMerit
Domain experts for the age of expert data Headquarters: USA / India (founded 2012)
Language coverage (2025): Multilingual managed teams across text, audio, image, video, and DICOM Best for: Healthcare, autonomous vehicles, finance, and safety-critical NLP As the industry pivoted from commodity labeling toward expert-grade data in 2025, iMerit's long-standing model — full-time, trained, domain-skilled workforces rather than anonymous crowds — looked prescient. The company deepened its position in medical imaging, autonomous vehicle perception, financial NLP, and multilingual annotation for regulated industries, and continued to appear across independent 2025 rankings as the specialist of choice when accuracy, auditability, and domain knowledge outweighed raw volume.
Key strengths in 2025:
Managed specialist workforce: credentialed, full-time annotators aligned with 2025's expert-data shift.
Regulated-industry depth: healthcare (DICOM), finance, and government programs.
Mature QA operations: enterprise-grade quality pipelines and edge-case handling.
Multimodal multilingual reach: text, audio, image, and video across major world languages.
Verdict: The steady specialist that the industry's 2025 quality pivot vindicated.
7. Defined.ai
Ethical, licensed multilingual data in the year provenance went mainstream Headquarters: Seattle, USA / Lisbon, Portugal (founded 2015)
Language coverage (2025): Broad coverage with a specialty in low-resource languages and dialects Best for: Voice AI, speech recognition, and off-the-shelf multilingual datasets With copyright litigation over scraped training data intensifying through 2025, Defined.ai's marketplace of ethically sourced, consent-based, licensed speech and language datasets moved from nice-to-have to strategic necessity. Its catalog strength in low-resource languages and dialect diversity kept it the go-to for voice AI teams building beyond the world's top 20 languages, offering both instant off-the-shelf licensing and custom multilingual collection.
Key strengths in 2025:
Marketplace model: instantly licensable speech, dialogue, and evaluation datasets with clear provenance.
Low-resource language depth: rare dialect and minority-language coverage for global voice AI.
Ethical sourcing: consent-driven collection as data-provenance scrutiny peaked in 2025.
Hybrid flexibility: off-the-shelf catalog plus custom collection services.
Verdict: 2025's cleanest answer to the question every legal team started asking: 'where did this data come from?'
8. Sama
Ethical annotation, recertified and resurgent Headquarters: San Francisco, USA (founded 2008)
Language coverage (2025): Multilingual annotation via 5,000+ staff data experts in East Africa and beyond Best for: Computer vision, GenAI evaluation, ethically audited data programs Sama's differentiated model — 5,000+ on-staff data experts (not gig contractors) working from Kenya and Uganda with 50% women representation — gained fresh validation in June 2025 when the company was re-certified as a B Corporation with an improved impact score. As enterprises wrote responsible-AI sourcing requirements into procurement, Sama's full workforce traceability, disciplined QA, and growing GenAI evaluation practice kept it firmly on 2025 shortlists.
Key strengths in 2025:
Recertified B Corp: improved impact score in June 2025 — independently verified ethics.
Staff-based model: 5,000+ employed data experts with full traceability, not anonymous gig workers.
Computer vision strength: top-tier image/video annotation with expanding GenAI alignment work.
Impact leadership: 50% women representation and documented living-wage employment.
Verdict: The conscience of the industry — and in 2025, increasingly its procurement requirement.
9. Nexdata
The off-the-shelf multilingual library, now multimodal Headquarters: China (founded 2011)
Language coverage (2025): Hundreds of languages via 1M+ hours of speech and 800TB of image/video Best for: Rapid prototyping with ready-made multilingual speech and multimodal datasets Through 2025, Nexdata continued compounding its greatest asset: one of the world's largest pre-built AI training data libraries, exceeding 1 million hours of speech across country-specific language variants plus 800TB of image and video, supported by 20,000+ professional annotators and AI-assisted labeling delivering 30%+ efficiency gains. The company expanded aggressively into data for speech language models, VLMs, and embodied AI — positioning that would carry it onto major conference stages in 2026.
Key strengths in 2025:
Colossal ready-made catalog: 1M+ hours of multilingual speech; 800TB of vision data.
AI-assisted labeling: proprietary platform with 30%+ efficiency gains.
Multimodal expansion: SpeechLLM, VLM, and embodied-AI dataset development through 2025.
Flexible engagement: off-the-shelf licensing plus custom collection and curation.
Verdict: 2025's fastest route from idea to training run when the multilingual dataset already existed.
10. Shaip
Compliance-first multilingual data for healthcare AI Headquarters: USA / India Language coverage (2025): 60+ languages across text, audio, image, and video Best for: Healthcare AI, conversational AI, and de-identification-heavy projects Shaip held its healthcare-AI data niche firmly through 2025. Its multilingual clinical audio, medical text, and physician-grade annotation — wrapped in rigorous de-identification and PHI-handling pipelines — kept it the consistently recommended vendor across 2025 analyses whenever regulated documents and privacy-sensitive multilingual data were central to a program.
Key strengths in 2025:
Healthcare depth: clinical audio, medical text, and licensed-clinician annotation.
De-identification expertise: rigorous PII/PHI removal for regulated multilingual data.
Compliance-conscious delivery: built for HIPAA-style regulatory environments.
Multimodal services: speech collection, transcription, and NLP labeling in 60+ languages.
Verdict: The 2025 default for multilingual healthcare and privacy-critical AI data.
Quick Comparison at a Glance (2025)
Widest language coverage: LXT (1,000+ locales post-Clickworker), TELUS Digital (500+ languages/dialects), Appen (235+).
Best for frontier LLM/RLHF work: Surge AI (post-June), Scale AI (pre-June and for Meta-aligned or government work).
Best for regulated industries: iMerit and Shaip (healthcare), TELUS Digital (audited enterprise programs).
Best for voice and low-resource languages: Defined.ai and Appen.
Best for ethical sourcing: Sama (recertified B Corp) and Defined.ai (licensed marketplace).
Biggest 2025 storylines: the Meta–Scale deal and client exodus, Surge AI's rise, and LXT's completed Clickworker integration.
Honorable Mentions Toloka (the Amsterdam-based crowd platform continuing its 2025 pivot from microtasks to expert LLM data), Mercor (the fast-rising expert-data marketplace that picked up post-Scale business), Centific (the NVIDIA-partnered 'data foundry' that raised $60 million in 2025 for multilingual, multimodal data), DATAmundi (the new brand of Summa Linguae Technologies, launched April 2025), and CloudFactory, Cogito Tech, and DataForce by TransPerfect all delivered credible multilingual capability just below the 2025 top-10 cut.
Epilogue: What 2025 Changed Forever 2025 settled an argument the industry had been having for years: the product is trust, and the future is expertise. The Meta–Scale deal proved that neutrality — not headcount, tooling, or price — is the decisive variable for frontier-lab customers. Surge AI's bootstrapped billion-dollar run proved that a smaller cohort of vetted multilingual experts can out-earn an army of microtaskers. And LXT's integration proved consolidation works when locale coverage is the prize. By year's end, the market had split cleanly into an expert-data tier (Surge, Mercor, and the specialists) and a scale tier (Appen, TELUS Digital, LXT) — the structure that would define 2026.
References & Sources All facts, figures, and rankings in this article were compiled from the following sources, accessed in August 2026:
"Top 10 Human Data Providers: Full In-Depth Review (Meta–Scale deal details, Surge AI $1.2B 2024 revenue, LXT–Clickworker timeline, TELUS Digital October 2025 privatization)." HeroHunt.ai. https://www.herohunt.ai/blog/top-10-human-data-providers-full-in-depth-review/ 2. "Scale AI Competitors 2026: 10 Vendors Compared by Fit (June 2025 Meta deal, Google ~$200M contract, client exodus, 14% layoffs, Surge revenue comparison)." 100signals. https://100signals.com/insights/scale-ai-competitors/ 3. "Meta Beefs Up AI Division with Scale AI Investment ($29B valuation, 49% stake, Wang departure)." Ars Technica, June 2025. https://arstechnica.com/ (via tagteam.harvard.edu/hub_feeds/3415/feed_items/14091720)
"Top 10 Human Data Labeling Providers (Meta ending TELUS content-moderation contract April 2025; Surge AI 50,000 expert contractors; Sama B Corp recertification June 2025, 5,000+ staff)." PIN-COM. https://pin-com.ghost.io/human-data-labeling-providers/ 5. "Top 10 Data Annotators for AI Labs: 2026 Benchmark (post-Meta-deal market reordering; Centific $60M 2025 raise)." HeroHunt.ai. https://www.herohunt.ai/blog/top-10-data-annotators-for-ai-labs-2026-benchmark/ 6. "Scale AI Competitors: Who Won the Data Market After the Meta Deal (Surge AI frontier crown, Mercor expert-data rise, neutrality analysis)." Teahose. https://www.teahose.com/guides/scale-ai-competitors 7. "Scale AI Alternatives: Labeling and Licensed Data (neutrality fallout; Google and OpenAI reducing reliance)." Troveo. https://www.troveo.ai/resources/scale-ai-alternatives 8. "Best Appen Alternatives (LXT–Clickworker integration completed July 31, 2025; 150+ countries, 1,000+ locales, 7M+ contributors; Appen financials)." AIMultiple. https://aimultiple.com/appen-alternatives 9. "Best Amazon Mechanical Turk Alternatives (LXT/Clickworker unified platform figures; pre-acquisition ~45 languages)." AIMultiple. https://aimultiple.com/amazon-mechanical-turk-alternatives 10. "Best Data Crowdsourcing Platforms (DATAmundi/Summa Linguae rebrand launched April 2025)." AIMultiple Research. https://research.aimultiple.com/telus-international/ 11. "TELUS Corporation FY2025 Filings (TELUS Digital 2025 operating results and corporate actions)." U.S. SEC EDGAR. https://www.sec.gov/Archives/edgar/data/868675/000110465925108121/tm2525674d2_ex99-1.htm 12. "AI Data Challenges Rise in 2024 AI Report (Appen: 1M+ contributors, 235+ languages)." Appen Press Release. https://www.appen.com/press-release/state-of-ai-2024 13. "Top 10 AI Data Collection Companies in 2025 (2025 vendor landscape: Lionbridge/TELUS multilingual scale, Defined.ai, Centific profiles)." SO Development. https://so-development.org/top-10-ai-data-collection-companies-in-2025/ 14. "Top 10 Multilingual Text-Data Collection Companies for NLP (vendor positioning: Surge AI senior cohorts, Shaip de-identification, LXT/iMerit breadth)." SO Development, September 2025. https://so-development.org/top-10-multilingual-text-data-collection-companies-for-nlp/ 15. "Best TELUS International Alternatives for AI Data Projects (LXT post-acquisition 6M+ contributors; TELUS Digital positioning)." Twine Blog. https://www.twine.net/blog/best-alternatives-to-telus-international/ 16. "Best 15 Data Collection Companies for AI Training (Appen, Nexdata, Sama, LXT company profiles; Nexdata 1M+ hours speech, 800TB vision data, 20,000+ annotators)." Unidata. https://unidata.pro/blog/best-data-collection-companies-for-ai-training/ 17. "Top Generative AI Training Data Companies (Sama 95%+ accuracy and B Corp status; Scale AI 240,000+ contractors; Defined.ai and Nexdata profiles)." Nexus Expert Research. https://nexusexpertresearch.co/blog/top-generative-ai-training-data-companies/ 18. "TELUS International Named a Leader in IDC MarketScape Data Labeling Vendor Assessment (500+ languages and dialects)." TELUS Digital Newsroom. https://www.telusdigital.com/about/newsroom/telus-international-leader-idc-marketscape-data-labeling-vendor-assessment-2023 19. "Best Multilingual Language Data Providers & Companies (Nexdata founding and services; Shaip services)." Datarade. https://datarade.ai/data-categories/multilingual-language-data/providers Note: This is a retrospective ranking compiled in August 2026 based on 2025-era company disclosures, contemporaneous reporting, and subsequent retrospective analyses. Statistics reflect figures reported during or about 2025 and may differ from current numbers.