HSP GRUPPE, a network of legally independent tax consulting, audit, and law firms across Europe and the UK, deployed ChatGPT Enterprise in a shared workspace with Kanzleipakt across 81 organizational groups, recording 500,000+ conversations over a six-month evaluation window from February 1 to July 14, 2026, with 98.6% of surveyed employees reporting improved productivity.
"Technology is moving faster than organizations can transform. Our challenge wasn't introducing AI, it was helping the organization absorb it," said Carsten Schulz, CEO of HSP GRUPPE. Managing Partner Frank Heibel, who uses ChatGPT to work through complex tax questions and refine client communications, said: "ChatGPT has become a genuine sparring partner. It completely changes the level at which you can work."
HSP GRUPPE had spent more than two decades standardizing processes, embedding quality management, and building a culture of continuous improvement across the network before generative AI arrived. Leadership reframed the rollout as an organizational transformation rather than a software deployment, with monthly AI Forums for sharing real-world use cases, governance and confidentiality controls around client information, and professional review and final responsibility retained by the relevant tax, legal, or accounting experts throughout.
Over the six-month evaluation window from February 1 to July 14, 2026, the deployment reached 755 weekly active users, 913 unique users, 500,000+ messages exchanged, and an 84% weekly active usage rate. The team is now moving from AI assisting individuals toward AI coordinating entire workflows, with a DATEV-focused AI team planned together with Kanzleipakt.
HSP GRUPPE deployed ChatGPT Enterprise in a shared workspace with Kanzleipakt spanning 81 organizational groups. Two custom shared agents were built on top: an AI Client Communications agent that drafts, structures, and aligns the tone of client communication, and a Booking Assistant SKR03 and SKR04 that supports the preparation and classification of specific booking questions. Professional review and final responsibility remain with the relevant tax, legal, or accounting experts in every case.
Across the network, 98.6% of surveyed employees report improved productivity and 84.6% report improved work quality, while 95.9% save time weekly — 63.5% saving at least two hours and 25.7% saving at least five hours. Partner Magdalene Posnak reduced the time needed to evaluate multiple real estate investments from nine hours to around two. An internal conservative-scenario estimate places additional annual capacity at roughly 40,000 hours across the firm network — about 28,000 productive (typically billable) hours and 12,000 in administration, client service, and support — implying a theoretical annual revenue potential of about €3.8M at conservative hourly rates, which the source flags as a capacity scenario, not realized or guaranteed revenue.
HSP is now piloting ChatGPT Work with a small group of developers and administrators before expanding it across the wider workspace, and is exploring how it could continuously review bookkeeping so that missing information is found long before year-end accounts are prepared. It plans to build a DATEV-focused AI, firm process and development team together with Kanzleipakt to convert decentralized experiments into documented, scalable reference workflows. "Everyone talks about AI replacing tax advisors. I think that's the wrong conversation. The real opportunity is helping qualified professionals become dramatically more effective," said Carsten Schulz.