Sotera Health Co (SHC) stock intrinsic value fair value estimate & owner earnings analysis

Sotera Health provides critical infrastructure services to the medical device and pharmaceutical industries through three segments: Sterigenics (contract sterilization, mostly using ethylene oxide gas and gamma/Cobalt-60 irradiation), Nordion (the world's leading supplier of Cobalt-60, used both by Sterigenics and by outside customers), and Nelson Labs (lab testing and advisory services for sterilization and microbiology). Its customers sign long-term contracts, often five to ten years and in some cases up to 39 years, because switching a sterilization method or provider requires new validation with the FDA, which makes the customer relationships very sticky. The central issue in valuing this business is ethylene oxide (EO) litigation. Sterigenics has been sued for years by people living near its sterilization facilities who allege injuries from EO emissions. In 2022 the company recorded a $408 million charge to resolve roughly 880 claims tied to its former Willowbrook, Illinois facility, which had already been closed since 2019; that settlement was paid out in 2023. Since then, the company settled a further $35 million of Georgia claims (2023) and roughly $65 million of additional Illinois claims (2025). We have treated the $408 million Willowbrook charge as a one-off tied to a specific, now-closed facility and excluded it when setting the normal earning level, but we have kept the smaller, recurring settlements in the years they were recognized, because this pattern of periodic EO settlements is a real, ongoing cost of running this business, not a one-time item to look past. On that basis, the normalized owner earnings per share is a median of 2021, 2023, 2024 and 2025 (2022 excluded as the distorted year). Three cases: Base case: revenue keeps growing at a modest mid-single-digit pace, slower than the last five years, reflecting the sticky long-term contract base. Capital spending is assumed to stay closer to the higher end of the last few years' range rather than falling further, both because new EPA emission-control rules for EO sterilizers (finalized in 2024, generally allowing two years to comply) will require facility upgrades, and because capital spending in the first half of 2026 has already come in well above the pace of 2025. Ongoing EO settlement costs continue at roughly the same scale as the last several years. Bear case: names two specific, dated risks that are not yet in the historical record. First, roughly 120 claims tied to the company's Vernon, California facility are scheduled for their first trials in January and April 2027; we have assumed a settlement of similar per-claim size to the 2025 Illinois settlements lands around that time. Second, in October 2025 the Georgia Court of Appeals sent a set of causation rulings back to the trial court after finding the wrong legal standard had been applied — rulings that had partly favored the company — reopening issues that looked resolved. The bear case also assumes slower revenue growth and capital spending staying elevated for emissions compliance. Bull case: leans on the company's actual courtroom record so far — a 2023 summary judgment win in New Mexico on the strict-liability and unfair-practices claims (upheld on appeal in 2024), and summary-judgment wins for the company in three Georgia "pool" cases in 2025 — to assume no new settlement of Vernon-scale claims materializes, growth returns toward the pace of the last five years, and capital spending settles near 2025's lower level as recent facility investments are fully utilized. Debt: the business carries roughly $2.1 billion of term loans and secured notes, both maturing in 2031, at a current cost of around 7.25%–7.375% — above the 6% rate used to value the business, so we added a modest amount to the debt figure to reflect that extra borrowing cost. After valuing the three cases and subtracting net debt (borrowings less cash), the estimates come to roughly $6 per share in the bear case, $11 in the base case and $14 in the bull case. Even in the bear case the business is still worth more than it owes, though not by a wide margin, which is the direct consequence of running a leveraged balance sheet alongside open litigation. Given the combination of leverage and litigation that is not yet fully resolved, the margin-of-safety price is set at a large discount to the base estimate, close to the bear-case outcome: about $6 per share. From that price, the base case implies a return above 20% a year as today's litigation and capital-spending questions are further resolved. One item we could not fully reconcile from the filings: capital spending in the first half of 2026 ran about 80% above the same period in 2025, a bigger jump than the emissions-compliance timeline alone would suggest; we have treated this as an early signal that capital spending may not keep falling as the 2025 full-year figure might have implied, rather than as a one-quarter anomaly.