$95.00
$230.41
bear $95.00
base $169.30
bull $230.41
margin of safety $90.00
market price* $384.02
West Pharmaceutical Services makes the rubber stoppers, plungers, seals and cartridge components that touch injectable drugs, plus self-injection devices made under contract for drug companies. Its Proprietary Products segment (about $2.5 billion of 2025's $3.07 billion of sales) sells standard and "high-value" components such as Westar, NovaPure, NovaChoice and Envision, many made with technology shared with Daikyo Seiko of Japan, in which West owns 49%. Its contract manufacturing segment (about $0.58 billion) assembles devices such as self-injectors for obesity and diabetes drugs. The core advantage is structural: once a component is named in a drug's regulatory filing, changing it means re-testing and re-filing, so West usually supplies a drug for its whole commercial life. That lock-in is why sales roughly doubled from $1.40 billion in 2015 to $3.07 billion in 2025 (about 8% a year, and about 7% a year in the 2015-2019 period before the pandemic). What the business earns. We measure the cash an owner could take out each year: operating cash flow, less working-capital swings, less stock compensation, less the capital spending needed to maintain the business. On that basis West earned $396 million in 2023, $249 million in 2024 and $392 million in 2025 ($5.26, $3.38 and $5.39 per share). The 2021-2022 years ($7.13 and $5.95 per share) were lifted by COVID-19 vaccine packaging and are not part of today's base. 2024 was the low point of the post-pandemic destocking, when customers worked down stockpiled components while West kept spending heavily on new capacity ($362 million in 2023 and $377 million in 2024). Because sales did not grow in those years, we counted all of that spending as upkeep, which makes the trough conservative. We also took out working-capital timing: in 2025 that removed a $70 million inflow, including $108 million from "other assets and liabilities" that the filing does not explain in detail; we treat it as timing, not earning power. Intangible amortization is tiny (about $3 million a year), so no wasting-asset adjustment was needed. Interest is negligible. We use the median of 2023-2025, which is the 2025 level of about $392 million, or about $5.53 per share on the roughly 71.0 million shares outstanding after this year's buybacks. It is a full cycle of the post-pandemic business: a normal year, the destocking trough, and the recovery. Recent trading supports the path rather than the level. In the first half of 2026, sales rose 17% to $1.72 billion and net income rose 32% to $293 million, led by high-value components for biologics, upgrades driven by the European Union's Annex 1 sterile-manufacturing rules, and elastomers for GLP-1 obesity and diabetes drugs. Operating cash flow fell because of a $189 million build in working capital, which we treat as timing. Owner cash grew 57% in 2025, a rebound from the trough; we assume only 8% for the coming year. Growth we credit, and what we leave out. The base case credits growth at or below West's demonstrated pace, because the mechanism is a long-running one: new injectable drugs are approved with West components specified in their filings, and existing drugs grow in volume. That mechanism kept working through the 2023-2024 destocking, when sales dipped only 1.9% for one year. We give no credit for higher margins from the shift to high-value products, a faster GLP-1 ramp, or any market expansion beyond that record. The SmartDose 3.5mL on-body injector business was sold to AbbVie for about $112.5 million; we do not count its proceeds beyond the cash already on the balance sheet. Bear case (about $95 per share). The risks are named in the filings. West's ten largest customers were 47.6% of 2025 sales, and one was over 10%. The company warns that customers could move to oral GLP-1 drugs or to drugs dosed less often. Sales of diagnostic devices made under contract are already falling. The case includes one full destocking downturn like 2023-2024, when owner cash fell 37% in a year: about $392 million next year, a drop to about $247 million, then a three-year recovery to the current level, 3% a year growth after that, and a 1% yearly decline for twenty years after year ten as the lock-in erodes, after which earnings hold flat. The business is worth about $6.4 billion in this case. Base case (about $169 per share). Owner cash grows 8% next year, 6% a year through year five, slowing to 3% by year ten. That is below the 7-8% sales growth of the last decade, and margins stay flat. After year ten, earnings grow 2% a year for twenty years and then hold flat. The case rests on the same lock-in mechanism continuing, which is the only part of the story we can see that far out. The business is worth about $11.7 billion. Bull case (about $230 per share). The company's own levers keep working: high-value component mix, Annex 1 conversions and biologics volumes. Growth is 12% next year, in line with the first half of 2026, then 9% a year through year five, close to the 8% sales record of 2015-2025. It slows to 5% by year ten, then 3% a year for twenty years before holding flat. The business is worth about $16.0 billion. Debt and cash. West owes very little: a $130 million term loan due July 2, 2027 and $73 million of 4.02% notes due July 5, 2027, plus about $4 million of finance leases, about $207 million in all. It held $436 million of cash at June 30, 2026, after spending $454 million on buybacks in the first half of the year. We set aside $100 million as working cash and count the rest, plus the $208 million book value of its equity stakes, chiefly the 49% of Daikyo. Daikyo's earnings are otherwise counted only through the small dividends it pays. After the debt, that adds about $337 million, or $4.74 per share, in every case. Equity is worth about $6.7 billion in the bear case, $12.0 billion in the base case and $16.4 billion in the bull case. The 2027 maturities are small next to roughly $400 million a year of owner cash and pose no refinancing risk in any case. Previous estimates for this company were made on a different basis and are not comparable. Margin-of-safety price: $90. How sure are we of the earnings level? Fairly sure. Three post-pandemic years range from $249 million to $396 million, and the low year came from a known, one-time combination of customer destocking and peak capacity spending. The worst plausible outcome we do not model is a lasting shift of GLP-1 treatment to pills together with the loss of a top customer. The business would survive it. It carries net cash and almost no debt, it has no controlling owner, and its components are written into the regulatory filings of a large number of approved drugs, but earnings could stay near the 2024 trough for years. If we are wrong on the two things most likely to go wrong, with growth of only 3% a year and upkeep spending staying at 2023-2024 levels, cutting the level to about $300 million, the shares are worth about $94. At $90, the business produces about $5.50 a share of owner cash today (about 6% of that price). It pays a dividend of $0.88 a year and buys back stock steadily, and that cash grows mid-to-high single digits on the record. That alone implies roughly 12-14% a year, so reaching 20% requires the share price to move toward the base-case value within about four years. The price assumes a holding period of about four years. At $90 the bear case and the low-growth scenario both imply roughly the starting value rather than a permanent loss. That protection against loss, more than any upside, is why the margin-of-safety price is $90 and not higher.