The legal profession is changing
Simmons & Simmons is proud to be leading the way with our development and adoption of Generative AI.
The firm employs the use of several AI applications and tools; chief among them is our own Percy AI – a truly unique Generative AI tool.
Named after one of the twin brothers who co-founded the firm, Percy is distinct from many of the typical tools deployed in the legal profession. Powered by a purpose-built Legal Inference Engine, it was meticulously developed in-house by the firm’s LLM team, led by partner and Global LLM lead, Drew Winlaw.
Simmons launched Percy in 2023, and began implementing it widely in 2024, following a firmwide AI upskilling programme for all employees. Several updates and versions of Percy have since been launched. The vast majority of Simmons employees now have nuanced AI skills – supported by access to an advanced firmwide Prompt Library.
Percy adoption has been widespread – at the beginning of 2025, 87% of fee earners at Simmons globally use Percy, while the tool sees around 5,000 daily prompts from our 2,500 international staff.
Percy AI has already begun to reshape how we operate. It has given our lawyers creative freedom, enabling them to find new ways of achieving routine tasks – whilst expanding their working methods.
Our AI advisory capabilities
Alongside our trailblazing in-house AI expertise, Simmons & Simmons has a large, thriving AI law practice.
Our experts in artificial intelligence law, regulation and policy have spent the last seven years building an international practice with deep industry knowledge.
Read more about our advisory work here.
Who can access Percy?
Percy is exclusively available to Simmons employees within our internal environment, offering added safety and security. As part of our AI Readiness service, we can demo Percy for you to help you scope and integrate AI throughout your own in-house operations. Our expertise isn’t just theoretical; it’s based on real experience.
To find out more or to book a demo, please get in touch.
News Story: Simmons’ AI tool Percy wins coveted FT AI innovation award
Percy AI, our generative tool, has been named the winner in the innovation in AI category at the FT Innovative Lawyers Awards
News Story: Simmons’ Generative AI tool Percy praised by Microsoft
In a recent article, Microsoft highlights the impact of our AI tool Percy on our business
Use cases
How AI is supporting our legal work, revolutionising the way we tackle complex challenges.
Financial services client: summarising legal obligations
Using generative AI to efficiently review and summarise complex legal texts, we provided our client, in the financial services industry, with accurate and relevant obligation summaries, giving them a clear understanding of their compliance requirements from across 53 jurisdictions for their financial obligations, and 11 jurisdictions as an employer.
This integration allowed our legal teams to focus on nuanced interpretations and applicable summaries rather than data preparation. A dashboard was developed by the team to consolidate the entire process into a single interface, automating data ingestion and aggregation across jurisdictions, allowing real-time review of AI-generated outputs alongside legal annotations. This supports scalability, enabling analysis of hundreds of thousands of rows in hours.
By streamlining the analysis and summarisation of legal obligations with AI, we significantly improved the speed and efficiency of the reviewing processes helping the client to navigate multiple complex regulatory landscapes.
Development project: rapidly analysing hundreds of public statements
We advised a client on a critical development project, where they were faced with over 400 public statements and objections relating to the project. To manage this sheer volume of information, we created and employed a custom programme through Percy allowing us to categorise objections by legal themes and perform gap analysis for our client.
We extracted the data from public statements, categorising them by legal themes and presenting them in a consolidated format. We then performed the gap analysis between each objection and the suggested course of action. This analysis checked whether all points of the objection were already addressed in expert recommendations relating to the project, aiding our lawyers during the review process.
Service Level Agreement (SLA) analysis for global media firm
We employed Percy to support a global media firm in identifying potential compensation opportunities from its suppliers. The use of generative AI enabled us to efficiently identify and extract service level agreements (SLAs) within the firm’s contracts: identifying obligations, performance criteria, breach indicators, penalties, and key dates. Detailed data requests were then produced to analyse whether the SLAs had been breached by specific suppliers.
Data Protection Impact Assessments (DPIAs) for pharmaceutical clients
Percy has been instrumental in streamlining the review process of Data Protection Impact Assessments (DPIAs) for clients in the pharmaceutical sector in Europe, significantly enhancing efficiency. One of their primary challenges is to determine whether various categories of clinical trial processing activities can be consolidated into fewer DPIAs. This complex analysis requires extensive manual comparison.
Our team used Percy’s advanced analytical capabilities to efficiently compare and review DPIAs, enabling them to review faster and deliver a superior product to the client with enhanced quality and reduced time investment. The use of Percy in this process resulted in time savings of 5-10 times compared to manual processes.
Non-disclosure agreement (NDA) Agent
In partnership with Flank AI, we’ve launched an NDA Agent to streamline the review and redlining of NDAs.
Operating as a "digital co-worker", the firm's sophisticated NDA agent can efficiently manage requests, mark-up documents and escalate more complex matters when necessary. Accessible through email, the agent offers a seamless integration into our existing workflows.
Other Simmons' agents in development with Flank include those specialising in Data Processing Agreements (DPAs), service agreements, and Investment Management Agreements (IMAs).
Unified Patent Court (UPC): AI monitoring and summarisation
Deploying Percy, we have made significant enhancements to our UPC activity monitoring process, significantly improving the efficiency and value of our reporting workflows used to advise clients.
Our lawyers now receive reports on UPC decisions and orders quicker than ever before, avoiding delays that could impact strategic decision-making.
Gen AI has also produced summaries, providing concise, accurate overviews of the key points in each UPC decision or order, meaning our lawyers can now quickly assess the relevance of each decision. This has delivered significant time savings and enhanced our strategic responses.
Key contacts
If you have any questions, contact a member of the Percy team for assistance:
