Ionis Pharmaceuticals Inc
Held by 1 superinvestor (IONS).
Educational data only — not investment advice. 13F positions are self-reported and can lag up to 45 days.
Valuation
Valuation · two methods
Earnings Power & Asset Floor
Two intrinsic-value methods and a tangible asset floor — deterministic, not price forecasts or recommendations.
High leverage — ranges are a degraded approximation (see method).
Zero-growth intrinsic ranges and a tangible asset floor — not investment advice, not a buy/sell signal, and not a price target.
Method & numbers
· reproduction $17.46
Moat Below asset base.
Graham earnings-power value (normalized NOPAT)
Normalized operating earnings net of maintenance capex are non-positive over the years shown; earnings power cannot be capitalized.
Normalized NOPAT = average operating margin over the years shown × latest-year revenue × (1 − normalized tax); then + D&A − maintenance capex (write A). Unlevered (pre-interest, attributable to all capital). Capitalized at the 9–11% rate band (read as a WACC proxy). Enterprise → equity bridge applied: + cash − total debt.
Years: 2025, 2024, 2023, 2022, 2021
v1 simplifications: Maintenance capex (degraded) deducted in full cash (write A): EPV = (NOPAT + D&A − maintenance capex) / WACC; no tax shield on the capex term. Capex doubled within two years (AI-hog rule): maintenance capex floored at 50% of current capex; EPV is correspondingly pressed down. Maintenance-capex methods diverge by 84% (> 50%); estimate is degraded. Capex doubled within two years (AI-hog rule): flagged; the spike is treated as growth, not maintenance — owner earnings carry extra uncertainty. Share-based compensation is left as a real expense (not added back).
Buffett owner-earnings value
Normalized owner earnings are non-positive over the years shown; earnings power cannot be capitalized.
Owner earnings = average net income + average D&A − maintenance capex (zero-growth floor; no ΔNWC). Levered (starts from net income, already after interest — an equity-holder stream). Capitalized at the 9–11% rate band (read as a cost-of-equity proxy). No enterprise→equity bridge: the capitalized result is already equity value (subtracting debt would double-count interest).
Years: 2025, 2024, 2023, 2022, 2021
v1 simplifications: Net income is below its multi-year average (cyclical/declining): normalized owner earnings anchored to the latest year — no peak-earnings capitalization (audit #2). Owner earnings = net income + D&A − maintenance capex (degraded); the working-capital change is excluded (maintenance ΔNWC ≈ 0; growth ΔNWC is carried in growth value, not double-counted). Capex doubled within two years (AI-hog rule): maintenance capex floored at 50% of current capex. One-time items are not separately normalized (multi-year averaging smooths them partially). Share-based compensation is left as a real expense (not added back); see the SBC/OE disclosure. Capitalized at the same 9–11% band as a cost-of-equity proxy (theoretically the cost of equity is higher; v2 simplification, v3 to refine).
Reproduction value = tangible net assets $489.09M + capitalized R&D $2.30B（FY 2025, 2024, 2023, 2021） = $17.46 / sh. Total book value (equity ÷ diluted shares) + capitalized R&D; intangibles not separated — goodwill/intangibles unavailable this period.
Moat reading: Franchise test compares earnings power (EPV) against reproduction value (tangible net assets + capitalized R&D). EPV well above reproduction value signals a moat; near it, a commodity; below it, value destruction. A directional reading, not a verdict.
Growth value gated to zero — no moat / ROIIC ≤ WACC, so no growth value is credited.
Window FY 2025, 2024, 2023, 2022, 2021 · discount band 9%–11% · normalized tax 0% (Average effective tax rate over 5 year(s), capped at the statutory 21%.) · diluted shares.
High leverage (net debt / shareholders' equity above 1.0): the single 9–11% rate band is a low-leverage / net-cash approximation and is directionally distorted here. The ranges are shown but should be read as degraded.
Ownership · 13F consensus
Who's buying it
Institutional ownership aggregated across funds — consensus strength and this quarter's moves. Describes actions, not advice.
1 superinvestor hold it · $170.9M combined
Largest holder Tweedy, Browne
Held by 1 superinvestor of Ionis Pharmaceuticals Inc (IONS); this quarter 1 trimmed, 1 exited (as of 2026-03-31).
13F positions are self-reported and can lag up to 45 days. Informational only — not investment advice.
Next · is it cheap
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Browse all valued stocks, ranked by value bandSuperinvestors Holding This Security
- Value$170.9MWeight (prev→now)15.7% → 13.6% ▼
Ownership overview
Ionis Pharmaceuticals Inc (IONS) is held by 1 of the superinvestors tracked on Compounder, with a combined $170.9M in reported 13F value. The largest position belongs to Tweedy, Browne, where it makes up 13.6% of the portfolio.
Over the latest quarter, 0 of the tracked filers opened a new position in IONS, 0 added to existing ones, 1 trimmed, and 1 sold out entirely.
Holder counts and values reflect the most recent SEC Form 13F filings, through the quarter ended 2026-03-31. Source: SEC EDGAR. A 13F shows only long US-listed positions and can lag the real portfolio by up to 45 days, so this is disclosed long ownership, not a complete picture.
Holders over time
Superinvestors holding this security over the last 8 quarters: 1 → 1.
Early quarters may understate holder counts due to data backfill — read the slope with care.
Sources· SEC EDGAR 13F as of 2026-03-31 · filed 2026-05-15
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