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Protagonist Therapeutics Inc

PTGXAbove valueExpectations · demanding

Held by 3 superinvestors.

Price$154.94
Holders3
Total value$29.5M

SEC 10-K · fundamentals

Business quality

as of 2025-12-31

Valuation basis: trailing twelve months to 2026-06-30 — latest 10-K plus unaudited 10-Q filings.

Revenue growth
-89.4%
Net margin
-282.8%
ROE
-21.2%
FCF margin
121.9%
Revenue $28.6M → $46.0M · 6y
What makes a business high quality

Valuation · value band

Above fair value

$1/ sh · growth-anchored intrinsic value
margin of safety
fair value
above fair value
$155
cheaperpricier

Zero-growth floor

$17

Central IV

$1

Optimistic top

$17

Protagonist Therapeutics Inc (PTGX): A conservative value band $17 / sh (zero-growth floor to growth-capped optimistic top); central read about $1. Today’s price sits above that band (price $155 as of 2026-08-19).

The middle figure is the main read. The right end is the optimistic case under the same conservative caps — not an absolute ceiling.

Revenue growth 5% (lower of historical trend and fundamental cap, capped by moat) · moat 0 yr · discount 10.6% · Zero-growth downside $17

Price as of 2026-08-19 · yahoo · DGS10 4.7% @ 2026-08-18.

Method & numbers

Model cautions

  • Owner-earnings yield diverges sharply from the 10-year Treasury (over 300 bps).

A conservative intrinsic-value band (zero-growth floor to growth-capped DCF) plus a tangible asset floor — not investment advice, not a buy/sell signal, and not a price target.

Owner-earnings DCF $0.63 – $1.17 · Greenwald zero-growth $16.52 · zero-growth base $16.52 · reproduction $16.52

Moat Below asset base · terminal value 48% of present value · owner-earnings yield 0% vs 10Y 4.7%.

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: TTM 2026-06-30, 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. Maintenance-capex methods diverge by 215% (> 50%); estimate is degraded. Share-based compensation is left as a real expense (not added back).

Buffett owner-earnings value$0.61 – $0.74 / sh

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: TTM 2026-06-30, 2024, 2023, 2022, 2021

v1 simplifications: 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). Maintenance-capex methods diverge by 215% (> 50%); estimate is degraded. 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 9–11% band as a cost-of-equity proxy; no leverage premium applied (net cash or debt within the no-charge range).

Reproduction value = tangible net assets $841.54M + capitalized R&D $331.35M（FY 2026, 2024, 2023, 2022） = $16.52 / 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. Dual reproduction test unavailable (intangibles not separated). A directional reading, not a verdict.

Growth value gated to zero — no moat or ROIIC ≤ WACC, so no growth value is credited.

Window TTM 2026-06-30, FY 2024, 2023, 2022, 2021 · discount band 9%–11% · normalized tax 1% (Average effective tax rate over 5 year(s), capped at the statutory 21%.) · diluted shares.

Owner-earnings DCF: growth g₁ 5% · OE FY TTM 2026-06-30, 2024, 2023, 2022, 2021 · Discount band: 9.21%–12.00% (DGS10 +4.5% to a 12% strict end, as of 2026-08-18). No enterprise→equity bridge: owner earnings already flow to shareholders (post-interest), so no net cash is added and no debt subtracted — matching the engine owner-earnings lamp.

Valuation basis: trailing twelve months to 2026-06-30 — latest 10-K plus unaudited 10-Q filings.

What the price is betting

Today's price pencils in about over 30.0% (outside the usual range) a year in owner-earnings for the next few years. Revenue actually grew 38.8% a year.

The market wants it well ahead of its own track record.

Roughly, the price needs its historical revenue growth to run about 23 more years to hold up.

How to read intrinsic value

SEC 13F · holders

Superinvestors Holding This Security

3 holders · $29.5M combined · this quarter +0 opened / -0 exited

This quarter2 added1 trimmed
Holders 1 → 3 · last 5q

SEC 13F · notes

Written summary

Protagonist Therapeutics Inc (PTGX) is held by 3 of the superinvestors tracked on Compounder, with a combined $29.5M in reported 13F value. The largest position belongs to Stanley Druckenmiller, where it makes up 0.6% of the portfolio.

Other notable holders by value include Polen Capital (0.0% of its book) and Ray Dalio (0.0% of its book).

Over the latest quarter, 0 of the tracked filers opened a new position in PTGX, 2 added to existing ones, 1 trimmed, and 0 sold out entirely.

Holder counts and values reflect the most recent SEC Form 13F filings, through the quarter ended 2026-06-30. 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.

How to read a 13F

SEC 13F · co-ownership

Also held by these investors

Investors holding Protagonist Therapeutics Inc (PTGX) also commonly hold →

PTGX's price is not below its conservative value band. See current strike-zone stocks

Also on

Sources· SEC EDGAR 13F as of 2026-06-30 · filed 2026-08-14

Educational data only — not investment advice. 13F positions are self-reported and can lag up to 45 days.

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