Member of Technical Staff, Research Scientist

Crosby is built on a simple conviction: a great legal system is the watermark of a great society — and the best legal work comes from combining human expertise with the right technology, not replacing one with the other.

Crosby is the first AI-native law firm, helping ambitious companies like Cursor, Ramp, and Cognition sign commercial contracts faster.

Legal work is both art and science, and we're mapping the frontier between the two — codifying what can be systematized, amplifying human judgment where it matters most. That's why the right way to bring AI into law isn't to sell software and walk away. It's to own the outcome together: higher-quality work, delivered faster. We build proprietary tools and human-in-the-loop workflows that change what's possible for corporate legal teams.

Crosby was founded by Ryan (Stanford Law, Cooley, startup GC) and John (Penn, first 15 engineers at Ramp). We work together, in person, in New York City — because the best ideas still happen in the same room. Help us transform one of society's most important industries.

As an AI Researcher at Crosby, you'll push the boundaries of what's possible with legal AI today. Using Crosby's accrued contract data, you'll develop novel methods for training, retrieval, and reasoning in a non-verifiable domain like contract review. You'll explore, develop, and apply state-of-the-art techniques in LLMs and applied NLP to improve how our platform understands, analyzes, and reasons over complex legal documents.

You’ll work closely with engineers, data scientists, and legal experts to translate research ideas into production systems. This role is for someone who is deeply curious, technically rigorous, and motivated to push the boundaries of what AI can do in high-stakes domains.

We also publish our work on legal AI at intelligence.crosby.ai — take a look at the kinds of problems you'd be working on.

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  Advance model capabilities: Research and develop novel approaches that measurably improve performance on tasks like document understanding, clause extraction, reasoning, and negotiation.

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  Develop training methods for non-verifiable domains: Create new methods for scalable training and RL in non-verifiable domains like contract review, spanning reward design, generators, and formal verification.

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  Experiment and iterate: Design and run rigorous experiments across architectures, prompting strategies, fine-tuning approaches, and retrieval methods, with results that hold up under scrutiny.

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  Improve evaluation: Develop benchmarks, datasets, and evaluation frameworks that define what good looks like for legal AI—including playbook formatting and retrieval and docx editing.

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  Bridge research and production: Work closely with engineering teams to hand off research insights in a form ready to scale into production.

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  Leverage modern AI techniques: Stay at the frontier of LLMs and applied AI, incorporating new methods where they meaningfully improve outcomes.

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  Collaborate cross-functionally: Partner with engineering, product, and legal teams—including working directly with attorneys to ensure results are of high legal quality.

• 3–7+ years of experience in AI research, machine learning, or applied NLP, with a strong foundation in deep learning and statistical methods.

• Hands-on experience working with LLMs, transformers, RL, and modern NLP techniques.

• Proven ability to run and evaluate experiments in a structured, rigorous way—thoughtful about both quantitative and qualitative outcomes.

• Ability to turn ambiguous, open-ended problems into concrete research directions, backed by strong independent research skills (e.g., multiple published first-author papers).

• Proficient in Python and ML frameworks such as PyTorch, TensorFlow, or similar.

• Able to deeply engage with legal concepts and collaborate with attorneys to ensure high legal quality. Prior legal experience is not strictly required.

• Effective communicator who can collaborate across technical and non-technical teams.

• Curious, driven, and excited about applying research to real-world, high-impact problems.

Crosby is an equal opportunity employer. We do not discriminate based upon race, religion, color, national origin, sex (including pregnancy, childbirth, reproductive health decisions, or related medical conditions), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, genetic information, political views or activity, or other applicable legally protected characteristics.

Background checks for applicants will be administered in accordance with applicable law, and qualified applicants with arrest or conviction records will be considered for employment consistent with those laws, including the New York City Fair Chance Act.

Pursuant to New York Labor Law Section 194-b, the US Pay Range for this position is listed in the job post. Final compensation will be determined based on skills, experience, and qualifications.