Value Investor
Start free

Passage BIO

PASG on Nasdaq. Market value $13m.

Watch this stockFree. We tell you when something changes.

Should I look at this?

Look carefully before going further

Why it could be worth it

Nothing stands out yet.

What to watch out for

Read the warning sign in its own filings

This is not advice.

Compare with another stock

Who owns it

None of the long-term investors we follow own it. 30 funds in all.

Jun '25
Dec '25
Jun '26
Largest holders overall

From 13F filings for the quarter ended 30 June 2026.

Big holders and activists

4 investors own more than 5%.

  • at least 21.0%+1.4 pts
    (filed with 1 related holder)
    Since 25 June 2026
    What they said

    The Reporting Persons originally acquired the securities reported herein because they believe the securities are undervalued and represent an attractive investment opportunity and they continue to hold the shares of Common Stock reported herein for investment purposes. The…

    Read the filing
  • WESTON NICHOLS
    Passive investor
    19.6%+4.6 pts
    Since 30 September 2025
  • Baselake Partners, LP
    Passive investor
    at least 7.3%
    (filed with 2 related holders)
    Since 18 June 2026
  • ORBIMED ADVISORS LLC
    Passive investor
    at least 4.3%−3.6 pts
    (filed with 1 related holder)
    Since 22 July 2025
    What they said

    The Reporting Persons from time to time intend to review their investment in the Issuer on the basis of various factors, including the Issuer's business, financial condition, results of operations and prospects, general economic and industry conditions, the securities markets in…

    Read the filing
  • Vestal Point Capital, LP
    Passive investor
    Sold down below 5%
    Since 30 June 2026
  • ORBIMED CAPITAL LLC
    Passive investor
    Sold down below 5%
    Since 20 December 2024
    What they said

    The Reporting Persons from time to time intend to review their investment in the Issuer on the basis of various factors, including the Issuer's business, financial condition, results of operations and prospects, general economic and industry conditions, the securities markets in…

    Read the filing

From Schedule 13D and 13G filings: anyone owning more than 5% must file one.

What insiders did

No insider bought shares on the open market in the last 12 months. 2 sold $113,185.

  • Borthwick Kathleen
    CFO
    Sold
    Date
    8 January 2026
    Shares
    2,062
    Price
    $18.44
    Value
    $38,023
  • Chou William
    PRESIDENT AND CEO, Director
    Sold
    Date
    8 January 2026
    Shares
    4,076
    Price
    $18.44
    Value
    $75,161

From Form 4 filings: insiders must report trades in their own company's shares within two days.

Warning signs in its filings

Problems the company itself reported to the SEC, in its own words.

1 serious warning sign in Passage BIO’s filings.

We look for five warning signs: doubt it can keep going, weak checks on its own accounts, a notice that its past accounts can't be relied on, a change of auditor, and one customer bringing in a big share of sales. We don't check lawsuits, investigations or debt yet.

We checked the auditor's report, internal controls, restatement notices, auditor changes and big customers in the 10-K filed 3 Mar 2026, plus the 10-Q filed 10 Aug 2026 and 7 later 8-Ks.

  • Doubt it can keep going

    Serious

    The company or its auditor warned it may not have enough money to last the next year.

    “As a result, there is substantial doubt about the Company’s ability to continue as a going concern within one year after the date that these consolidated financial statements are issued.”
    Show the full paragraph
    As a result, there is substantial doubt about the Company’s ability to continue as a going concern within one year after the date that these consolidated financial statements are issued. The consolidated financial statements do not include any adjustments to the carrying amounts and classification of assets, liabilities, and reported expenses that may be necessary if the Company were unable to continue as a going concern.

    From the 10-Q filed 10 August 2026, Part I, Item 1. Financial Statements. Read it in the filing

A 10-K is the yearly report every US company files with the SEC. An 8-K is a short notice of a big event.

The deep dive

Everything above is arithmetic on public filings. The deep dive reads the last ten years of annual reports, the proxy statements, and the earnings calls, then argues the case the way Buffett, Klarman, and Hohn would, and checks every claim against the source.

  • What the business is worth, as a range, and the margin of safety at today’s price
  • Prices to start buying, buy, and buy hard
  • The three things that would make this a mistake
  • Every number footnoted to the filing it came from
Create a free account to run it

Your first deep dive is free.

What a finished deep dive looks like

Not advice. Numbers on this page come from SEC filings and are updated each night; prices are updated again after the US market closes. The five-year figures are rounded.