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Greater London, England, United Kingdom
Onsite
Mercor's mission is to organize human intelligence to power the AI economy. We're a leading AI data company, building the layer between human expertise and frontier models. Millions of domain experts on the platform are paid over $4 million per day to train frontier AI models. Mercor's APEX benchmark family measures AI's real-world impact on professional work. Mercor Enterprise brings this same infrastructure to Fortune 500 companies: helping companies capture how their best people actually work, translating that expertise directly back into agents.
Mercor is creating a new category of work where expertise powers AI advancement. Achieving this requires an ambitious, fast-paced and deeply committed team. You’ll work alongside researchers, operators, and AI companies at the forefront of shaping the systems that are redefining society. Mercor is a profitable Series C company valued at $10 billion. We work in-person five days a week in our San Francisco, NYC, or London offices.
Silicon Valley’s leading AI companies partner with Mercor to scale high-quality data operations. As an SPL, you will:
Drive the tactical execution of multi-million-dollar projects.
Build deep client relationships with researchers at top AI labs.
Orchestrate the work of 1,000+ contributors.
Ensure flawless operational execution under demanding timelines.
This is a hands-on operations role for candidates excited by process optimization, rapid iteration, and high-intensity problem solving. We're an early-stage startup that operates with intensity. That means occasionally being responsive on weekends and always holding a high bar for output. The upside — performance incentives, career trajectory, and meaningful equity — reflects that.
Design and manage end-to-end data pipelines, from customer specifications to final delivery.
Diagnose bottlenecks, restructure workflows, and implement solutions that improve quality, throughput, and cost-efficiency.
Examples include: creating incentive systems, re-sequencing workflows, refining instructions, and scaling review processes.
Act as the primary point of contact for leading AI labs.
Deliver clear, consistent reporting and proactively anticipate client needs.
Build long-term trust and identify opportunities for expansion.
Manage 1,000+ distributed contributors in Slack-based workspaces.
Source, vet, train, and performance-manage domain experts.
Maintain high execution standards across all stages of production.
Run daily internal syncs (“war rooms”) to stay ahead of issues.
Provide regular, transparent progress updates to customers.
Experience: Background in consulting, finance, startups, or other operationally intense environments.
Skills: Strong analytical and communication abilities; proven track record of managing complex projects.
Customer-Facing Experience: Comfortable working directly with high-profile clients.
Mindset: Excited by “gritty” process optimization and large-scale execution.
SPLs generate $10M+ in project revenue annually.
In-office Mon–Fri
Customer requests are high-pressure and time-sensitive (e.g., onboarding 1,000 contributors in 3 days, delivering 10+ hours of quality data per contributor within 48 hours).
The role is explicitly operations-focused—not strategy, product, or GTM.
SPLs begin as individual contributors, running projects end-to-end.
High performers may advance to Senior SPL (SSPL) roles, managing multiple projects and teams of SPLs.
Base cash comp from £89,500 to £111,900 for SPL, £111,900 – £149,200 for SSPL
Aggressive bi-annual performance bonus structure
Generous equity grant vested over 4 years
£8K proximity bonus (if you live within 0.5 miles of our office)
£1.2K monthly stipend for meals
Free Gym membership
£160 monthly laundry reimbursement
£160 monthly personal wellness reimbursement
Private medical, dental insurance
Income protection, group life assurance, and critical illness cover
Pension with company match
We consider all qualified applicants without regard to legally protected characteristics and provide reasonable accommodations upon request.
