Harrogate health care practice Leonard Oates has been swallowed up by one of Leeds' largest commercial law firms, Walker Morris.
Leonard Oates' six partners all moved to Walker Morris, effectively marking the end of the firm.
Andrew Oates, ex-Leonard Oates partner, said the firm's partners saw a need for a broader support network to fully use their expertise.
They decided Walker Morris, which has 29 partners and 164 other lawyers, could offer this support.
"Walker Morris did not buy the firm, they offered posts to all members of staff," said Oates.
None of the lawyers join Walker Morris as partners.
Oates has joined the clinical negligence group in the firm's litigation department. The department has also secured Dagmar Leonard, Paul Richards and Christopher Mordue. To its commercial department, Walker Morris has added Paul Neal, and Gavin Cleworth has gone to its intellectual property department.
All six lawyers will maintain their health focus, representing NHS clients.
Before forming Leonard Oates, the six lawyers worked with the in-house legal department at the Northern and Yorkshire Regional Health Authority.
Walker Morris managing partner Peter Smart said the firm had advised health authorities and trusts on a variety of commercial issues, including hospital disposals, project finance, planning and information technology.
Smart said: "The enlarged health sector group will be in a position to provide a comprehensive legal service to the health sector, spanning an enormous range of skills, from public finance initiative transactions through information technology contracts to clinical negligence."