Florida Cancer Specialists & Research Institute is owned by its physicians. More than 250 oncologists hold membership interests in the practice, which is organized as a professional limited liability company under Florida law and operates nearly 100 clinic locations across the state. The ownership picture gained a second layer in June 2025, when McKesson Corporation paid about $2.49 billion for a roughly 70% controlling interest in Core Ventures, the separate company that handles FCS’s administrative operations.1McKesson. McKesson Corporation Completes Acquisition of Core Ventures The medical practice itself did not change hands.
Who Owns the Medical Practice
FCS is registered as a Florida LLC under Chapter 621, the statute that governs professional service corporations and professional limited liability companies. Chapter 621 restricts ownership of a professional LLC to individuals licensed to perform the service the company was formed to provide. For a medical practice, that means only physicians licensed in Florida can hold membership interests in FCS.2The Florida Legislature. Florida Code 621 – Professional Service Corporations and Limited Liability Companies
A physician typically joins FCS as an employed associate and, after a period of evaluation, may be offered the chance to buy equity. The specific financial terms, eligibility criteria, and buy-in process are set out in internal agreements that FCS does not disclose publicly. What the statute requires is clear: outside investors, private equity firms, and hospital systems cannot own any part of the practice itself. If a physician leaves, retires, or loses their license, they can no longer hold a membership interest.
The practical consequence is that the people making clinical decisions at FCS clinics are, in most cases, either owners of the practice or working directly alongside owners who see patients themselves.
What McKesson Actually Bought
On June 2, 2025, McKesson completed its acquisition of an approximate 70% controlling interest in Community Oncology Revitalization Enterprise Ventures, LLC, known as Core Ventures. McKesson paid about $2.49 billion for that stake, and FCS physicians retained the remaining 30%.1McKesson. McKesson Corporation Completes Acquisition of Core Ventures
Core Ventures is not the medical practice. It is a separate legal entity that FCS created to run its non-clinical operations: billing, procurement, human resources, technology, and data analytics. McKesson now controls that administrative infrastructure. FCS as a medical practice remains independently physician-owned.3Florida Cancer Specialists & Research Institute. McKesson Signs Agreement to Acquire Controlling Interest in FCS’s Core Ventures
As part of the deal, FCS joined McKesson’s US Oncology Network, which supports more than 700 sites of care across 29 states. Membership gives FCS access to McKesson’s practice management tools, clinical research infrastructure, payer strategy resources, and precision medicine programs.4McKesson. US Oncology Network – Advancing Local Cancer Care
Why the Two-Entity Split Matters
The legal distinction between the practice and its administrative arm is real, and it is also what makes the ownership story harder to summarize in a single sentence. McKesson cannot direct patient care decisions and cannot own the practice. It can, however, shape the business environment the practice operates in. The entity that handles FCS’s revenue cycle, drug purchasing, and technology now reports to McKesson’s corporate leadership.
For a patient, the care relationship with an FCS oncologist has not legally changed. The physician treating you is still part of a physician-owned group, still bound by the same licensing and malpractice framework, and still accountable to a board of doctors elected by their peers. The business machinery behind that care now sits inside a different corporate structure than it did before mid-2025.
How the Current Structure Came Together
Before Core Ventures existed, FCS had a different administrative affiliate. In 2017, FCS leadership incubated the American Oncology Network (AON), a management services organization built to extend FCS’s internal administrative capabilities to smaller oncology practices. FCS physicians were investors in AON, and several FCS executives helped run the network.
That relationship ended around 2020, in the same period FCS announced it would pay a $100 million criminal penalty to the U.S. Department of Justice to resolve an antitrust charge involving a market allocation conspiracy with a radiation oncology practice in southwest Florida.5United States Department of Justice. United States of America v. Florida Cancer Specialists and Research Institute, LLC The deferred prosecution agreement that resolved the case expired at the end of 2023 without further charges against FCS as an entity, but it reshaped the practice’s leadership. The founder stepped away, FCS separated from AON, and FCS established Core Ventures as its own administrative services entity. Core Ventures later became the vehicle through which McKesson took its controlling stake. AON continues to operate independently and no longer has a relationship with FCS.
Who Runs FCS Day to Day
Governance of the medical practice sits with an Executive Board of physician leaders. The board includes one representative from each of FCS’s six geographic regions across Florida plus one at-large member elected to serve the statewide network. The current board was installed effective July 1, 2025.6PR Newswire. Florida Cancer Specialists and Research Institute Announces Installation of New Executive Board
Operational leadership runs through a professional management team led by CEO Ryan Ciarrocchi, with a chief operating officer, chief financial officer, general counsel, chief compliance officer, chief technology officer, and senior vice presidents overseeing payer strategy, clinical research, pharmacy services, and marketing.7Florida Cancer Specialists & Research Institute. Leadership Team The CEO reports to the physician board, which keeps the administrative leadership accountable to the owners of the practice. How that accountability interacts with McKesson’s control of the administrative services entity is something the physicians and McKesson will work out under their partnership agreements.
The short version: FCS physicians own the practice. McKesson owns most of the company that supports it. Both statements are true at the same time, and the difference between them is the whole story of who owns Florida Cancer Specialists today.