Key Takeaways
- • California's Office of Health Care Affordability (OHCA) finalized regulations implementing AB 1415, effective November 2, 2026, clarifying how healthcare transaction notice requirements apply to private equity groups, hedge funds, and management services organizations (MSOs).
- • Private equity and hedge fund acquisitions of 10 percent or more of a healthcare entity's or MSO's assets, equity, debt, or liabilities may be a material change transaction, down from the 5 percent threshold in the May 2026 proposal, but only if the target meets the applicable filing criteria.
- • Acquisitions below 10 percent can still trigger filing if the investor obtains specified rights such as board appointment, veto, or indebtedness authority.
- • Venture financings are not automatically exempt: California's definition of private equity group does not expressly carve out venture capital, and transfers of 25 percent or more of governing-body voting power, or supermajority or veto rights, can constitute material change transactions.
- • Newly covered filers face expanded disclosure obligations and a 90-day notice period, and parties should plan early for potential Cost and Market Impact Review (CMIR).
Summary
California's Office of Health Care Affordability has finalized regulations implementing Assembly Bill 1415, which expanded the state's healthcare transaction notice regime effective January 1, 2026 to cover private equity groups, hedge funds, MSOs, newly created entities, and entities that own, operate, or control providers. The final rules, which follow proposed regulations in May 2026 and revised proposals in September 2026, become effective November 2, 2026, according to Wilson Sonsini. The regulations set filing thresholds for these new noticing entities, identify additional material change transactions, and expand the information required in filings.
For private equity and hedge fund investments, the central change is a 10 percent threshold, which the May proposal had set at 5 percent. An investment crossing 10 percent of the assets, equity, debt, or liabilities of a covered healthcare entity or MSO is a material change transaction, and the rule captures groups of investors acting collectively. Crossing the threshold alone does not require a filing. The healthcare entity or MSO must also meet the applicable revenue, asset, or geographic criteria under Section 97435(b). Acquisitions below 10 percent may also qualify if accompanied by specified authority, such as the power to appoint leadership, veto decisions, control indebtedness, or charge fees.
Venture capital investors should not assume they fall outside the rules. The statutory definition of private equity group does not expressly exclude venture capital funds, unlike Massachusetts and Maine, which carve out early-stage venture investors. For later-stage venture and growth financings, a transfer of 25 percent or more of governing-body voting power, or supermajority or veto rights that amount to control, may trigger the general change-of-control provisions where the healthcare entity meets the $25 million revenue or California asset threshold, or $10 million where a qualifying counterparty is involved. Investments in an MSO alone do not trigger these provisions for venture-backed digital health companies using MSO-PC structures.
The regulations also establish two-part tests for MSOs. Filing is required only where the MSO falls within a defined category, such as certain hospital-owned MSOs or MSOs with specified physician or healthcare affiliations, and the transaction is a material change. Qualifying transactions include an MSO providing management services to a qualifying healthcare entity, providing services to two or more providers generating at least $10 million in annual California-derived revenue, or a transfer of control of a healthcare entity. A new management services agreement alone does not require notice.
Filer obligations are expanded. Private equity groups and hedge funds must disclose healthcare entities and MSOs they own, control, or finance, along with organizational charts and financial, valuation, governance, and portfolio information. The rules also add a trigger for certain sales or transfers of healthcare real estate where the surviving entity must lease or pay rent. Submitted information is generally a public record unless designated confidential and accepted by OHCA. Wilson Sonsini advises early screening, given the 90-day notice period and the possibility of a CMIR.
For private equity and hedge fund investments, the central change is a 10 percent threshold, which the May proposal had set at 5 percent. An investment crossing 10 percent of the assets, equity, debt, or liabilities of a covered healthcare entity or MSO is a material change transaction, and the rule captures groups of investors acting collectively. Crossing the threshold alone does not require a filing. The healthcare entity or MSO must also meet the applicable revenue, asset, or geographic criteria under Section 97435(b). Acquisitions below 10 percent may also qualify if accompanied by specified authority, such as the power to appoint leadership, veto decisions, control indebtedness, or charge fees.
Venture capital investors should not assume they fall outside the rules. The statutory definition of private equity group does not expressly exclude venture capital funds, unlike Massachusetts and Maine, which carve out early-stage venture investors. For later-stage venture and growth financings, a transfer of 25 percent or more of governing-body voting power, or supermajority or veto rights that amount to control, may trigger the general change-of-control provisions where the healthcare entity meets the $25 million revenue or California asset threshold, or $10 million where a qualifying counterparty is involved. Investments in an MSO alone do not trigger these provisions for venture-backed digital health companies using MSO-PC structures.
The regulations also establish two-part tests for MSOs. Filing is required only where the MSO falls within a defined category, such as certain hospital-owned MSOs or MSOs with specified physician or healthcare affiliations, and the transaction is a material change. Qualifying transactions include an MSO providing management services to a qualifying healthcare entity, providing services to two or more providers generating at least $10 million in annual California-derived revenue, or a transfer of control of a healthcare entity. A new management services agreement alone does not require notice.
Filer obligations are expanded. Private equity groups and hedge funds must disclose healthcare entities and MSOs they own, control, or finance, along with organizational charts and financial, valuation, governance, and portfolio information. The rules also add a trigger for certain sales or transfers of healthcare real estate where the surviving entity must lease or pay rent. Submitted information is generally a public record unless designated confidential and accepted by OHCA. Wilson Sonsini advises early screening, given the 90-day notice period and the possibility of a CMIR.
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