Who owns Corewell Health Laboratory Venture (Michigan JV entity, name as formed with Corewell Health)

Corewell Health Laboratory Venture (Michigan JV entity, name as formed with Corewell Health) - Profile

Diagnostic Lab of Michigan, LLC is the clinical laboratory joint venture formed by Quest Diagnostics and Corewell Health, the Michigan health system, and it completed its founding transaction on 5 January 2026. Quest contributes reference laboratory testing, professional laboratory management, analytics and workforce and supply chain services, while Corewell Health contributes its Michigan laboratory operations and its patient base, and the venture manages the laboratories across all 21 Corewell Health hospitals as well as outreach testing for physicians and patients in the state. It is building a 100,000 square foot laboratory at the Corewell Health Southfield Center in Southfield, Michigan, due to open in the first quarter of 2027 with automated microbiology and high throughput molecular testing, and the existing laboratories of both organisations continue to run until then.

The disclosed stakes

One row per position. Where a holder reports the same company in two share classes, both rows are shown rather than summed, because the class is part of a position's identity.

Where each figure comes from

A private stake has no ownership form behind it, so the source is always the holder's own filing or disclosure. Anything modelled says so, with the arithmetic.

• Quest Diagnostics Incorporated, as of 31 Jan 2026. Quest and Corewell Health (a Michigan health system) signed a definitive agreement in August 2025 to form a new entity performing laboratory testing in Michigan; the transaction closed in January 2026. Corewell Health contributed a laboratory business over which Quest obtained a controlling financial interest; ownership is 51% Quest / 49% Corewell Health, and Quest CONSOLIDATES the entity (confirmed operational: total noncontrolling interests jumped from $36 million at 31 Dec 2025 to $303 million at 30 Jun 2026 per the Q2 2026 10-Q balance sheet). This is the Nucor/Moody's ICRA/Corewell precedent from the research brief: a JV Quest consolidates while the hospital partner holds a real minority is a holding at Quest's OWN percentage (51%), not the reverse. value_usd is a MODELLED estimate, not a filed figure: the Q2 2026 10-Q states the total purchase consideration to Corewell Health included $38 million cash plus a 49% noncontrolling interest 'valued at $253 million.' Assuming per-unit value is consistent across the two ownership stakes (standard for a purchase-price allocation), implied total entity equity value = $253,000,000 / 0.49 = $516,326,531, so Quest's 51% stake = 0.51 x $516,326,531 = $263,326,531. Written as basis filed_10q / confidence estimated per the brief's rule on derived estimates, since the $263M figure itself is arithmetic, not a number the filing states directly for Quest's stake. BASIS CORRECTION by the coordinator before commit: this row was written as basis filed_10q with confidence estimated. The brief's rule 5 on derived estimates requires BOTH fields to change, 'set basis: modelled, confidence: estimated', and ends 'Never present a modelled figure as filed'. The $263,326,531 is arithmetic derived from the filing's $253,000,000 noncontrolling-interest fair value, not a figure the 10-Q states for Quest's own stake, so the basis is now modelled. The 51 per cent ownership percentage itself IS stated in the filings and is unaffected by this change. sourcesource 2