X4 Pharmaceuticals (XFOR): which funds own it
A 13F shows the portfolio at quarter-end and is filed up to 45 days later: these are not real-time positions and they may have changed.
Sections with a free account
6 concentrated managers hold it (−1 vs last quarter); combined they have held more shares for 4 quarters in a row (2 added, 1 trimmed). Its median weight in those portfolios is 1.4%. 1 officer or director bought in 6 months.
Who owns X4 Pharmaceuticals?
Holders that filed a Schedule 13D or 13G with the SEC for owning more than 5% of the shares: Morgan Stanley (13G/A filed Mar 6, 2026), Empery Asset Management (13G/A filed Jan 15, 2026), Coastlands Capital (13G filed Oct 3, 2025), Deep Track Capital (13G/A filed Aug 14, 2026) and Perceptive Advisors (13G/A filed Aug 14, 2026). As of Jun 30, 2026, the largest holders reported on Form 13F were Morgan Stanley (9.5 million shares), FMR (8.3 million shares) and Bain Capital Life Sciences Investors (8.0 million shares).
Which institutions hold the most X4 Pharmaceuticals shares?
Per Form 13F filings as of Jun 30, 2026:
- 1. Morgan Stanley: 9.5 million shares
- 2. FMR: 8.3 million shares
- 3. Bain Capital Life Sciences Investors: 8.0 million shares
- 4. Perceptive Advisors: 7.9 million shares
- 5. Saturn V Capital Management: 7.0 million shares
- 6. Empery Asset Management: 6.9 million shares
- 7. Deep Track Capital: 5.9 million shares
- 8. BlackRock: 5.6 million shares
- 9. Kalehua Capital Management: 3.7 million shares
- 10. Vanguard Capital Management: 3.7 million shares
Sources:13G/A by Morgan Stanley (Mar 6, 2026) ↗13G/A by Empery Asset Management (Jan 15, 2026) ↗13G by Coastlands Capital (Oct 3, 2025) ↗13G/A by Deep Track Capital (Aug 14, 2026) ↗13G/A by Perceptive Advisors (Aug 14, 2026) ↗All of the company's proxy statements on EDGAR ↗
We hold 13D and 13G filings made since Dec 23, 2024: a holder above 5% that has not filed since then does not appear here.
X4 Pharmaceuticals revenue
X4 Pharmaceuticals reported annual revenue of $6.5 million for fiscal year 2025 (year ended December 31, 2025), according to its Form 10-K filed with the SEC (XBRL data).
Quarter flow (concentrated managers)
Change in managers (7 → 6): 0 opened · 1 exited = −1
Net flow in the quarter: +$7.1M (+1.5 M shares) · bought $9.9M and sold $2.8MShares concentrated managers added minus those they cut, valued at the 13F quarter-end implied price, not each trade's price. It is a different measure from the change in managers: the two can have opposite signs.
Accumulation: combined they have held more shares for 4 quarters in a row (2 added, 1 trimmed). It is the combined share count of those still holding it: one large buyer can outweigh many who trimmed.
The set of concentrated managers changed between quarters: with the set as it was then, 8 held it last quarter (the chart point); with today's set, 7 (the base for the change).
Concentrated managers holding it
- Bain Capital Life Sciences Investors$37.2M2.2%
- Saturn V Capital ManagementIncreased$32.6M4.7%+0.3 pp
- Rosalind Advisors$15.0M5.6%
- BVF$10.4M0.3%
- Venrock AdviserIncreased$9.0M0.3%+0.2 pp
- Samsara BiocapitalReduced$6.5M0.5%−0.2 pp
Up to 15, sorted by position value. The percentage is the weight in each manager's portfolio.
Largest holders of XFOR (all 13F filers)
- Morgan Stanley9.5 MBank or trading desk · 9.27% of the company−5,713
- FMR8.3 MInvestment firm · 8.15% of the company+218 K
- Bain Capital Life Sciences Investorsconcentrated8.0 MInvestment firm · 7.80% of the company0
- Perceptive Advisors7.9 MType not verified · 7.77% of the company+1.2 M
- Saturn V Capital Managementconcentrated7.0 MInvestment firm · 6.83% of the company+517 K
- Empery Asset Management6.9 MType not verified · 6.79% of the company−2.0 M
- Deep Track Capital5.9 MInvestment firm · 5.76% of the company−461 K
- BlackRock5.6 MIndex manager · 5.44% of the company+4.3 M
- Kalehua Capital Management3.7 MType not verified · 3.65% of the company0
- Vanguard Capital Management3.7 MIndex manager · 3.64% of the company+218 K
- Shares
- 9.5 M
- Change
- −5,713
- % of the company
- 9.27%
See more
- Type
- Bank or trading desk
- Value
- $44.2M
- Shares
- 8.3 M
- Change
- +218 K
- % of the company
- 8.15%
See more
- Type
- Investment firm
- Value
- $38.9M
- Bain Capital Life Sciences Investorsconcentrated
- Shares
- 8.0 M
- Change
- 0
- % of the company
- 7.80%
See more
- Type
- Investment firm
- Value
- $37.2M
- Shares
- 7.9 M
- Change
- +1.2 M
- % of the company
- 7.77%
See more
- Type
- Type not verified
- Value
- $37.0M
- Saturn V Capital Managementconcentrated
- Shares
- 7.0 M
- Change
- +517 K
- % of the company
- 6.83%
See more
- Type
- Investment firm
- Value
- $32.6M
- Empery Asset Management
- Shares
- 6.9 M
- Change
- −2.0 M
- % of the company
- 6.79%
See more
- Type
- Type not verified
- Value
- $32.4M
- Shares
- 5.9 M
- Change
- −461 K
- % of the company
- 5.76%
See more
- Type
- Investment firm
- Value
- $27.5M
- Shares
- 5.6 M
- Change
- +4.3 M
- % of the company
- 5.44%
See more
- Type
- Index manager
- Value
- $25.9M
- Kalehua Capital Management
- Shares
- 3.7 M
- Change
- 0
- % of the company
- 3.65%
See more
- Type
- Type not verified
- Value
- $17.4M
- Shares
- 3.7 M
- Change
- +218 K
- % of the company
- 3.64%
See more
- Type
- Index manager
- Value
- $17.4M
The 10 13F filers with the most shares as of Jun 30, 2026, whatever their type (index firms usually come first). “Change”: shares added or cut versus the previous quarter, split-adjusted; “no data” = there is no comparable portfolio for the previous quarter (no filing, or a filing with its holdings under confidential treatment). “% of the company” only where shares outstanding are up to date. Entities of the same group file separately and some 13F filings include other managers: there may be double counting. With a free account: the top 25, the largest buyers and the largest sellers.
Fundamentals
12-month figures to Sep 30, 2026 · balance sheet as of Sep 30, 2026.
- Operating margin
- —
- Net margin
- —
- ROE
- -58.0%
- Revenue (TTM)
- $9.8M
- Revenue growth
- 69.0%
- Net income (TTM)
- $-80.5M
- Net debt / EBITDA
- —
- Free cash flow (TTM)
- —
- Quality vs sector
- —
Figures from the statements the company filed with the SEC (10-K, 10-Q). Free cash flow = operating cash flow − capital expenditures; empty if the company does not report capex. “Quality vs sector”: 0 to 100, the average of its percentiles in ROE, operating margin, free-cash-flow margin, revenue and earnings growth and net debt / EBITDA (at least 3 needed) against companies in its sector above $300M. How each figure is calculated
Shares outstanding: buybacks and dilution
2025: 42.3 M
There is a jump that may be an undetected split: we do not show the changes.
- Buybacks (FY 2025)
- no data
- Share issuance
- $239M
- Stock-based compensation
- $4.3M66.1% of revenue
- Dividends paid
- no data
From the statements the company filed with the SEC (10-K). The change compares average diluted shares of each fiscal year, on today's basis: negative = it bought back more than it issued; positive = dilution. “No data” = the company does not report that item under a tag we can read; it does not mean zero.
Earnings quality and debt
- Operating cash flow ÷ net income (12 months)
- no datanot calculated with negative net income
- Interest coverage (operating income ÷ interest)
- −9.8 timesnegative operating income
- Debt due within 12 months
- no data
- Year 1$0
- Year 2$76.7M
- Year 3—
- Year 4—
- Year 5—
- Later—
From the figures the company filed with the SEC. Cash flow over net income near or above 1 means earnings are collected in cash; far below, that part is accounting. Coverage says how many times operating income pays the latest fiscal year's interest. Maturities come from the debt note of the latest annual report, counted from its closing date. “No data” never means zero.
Insiders (Form 4)
10% owners who bought (6 m): 0
Open-market purchases, excluding 10b5-1 plans. Officers and directors only; joint filers of the same purchase count as one. 10% owners with no role are shown separately. 0 = nobody bought; “no data” = we do not have its Form 4 filings.
Each of the company's Form 4 filings, on EDGAR ↗Latest trades, with date and filing →
Above 5% (13D/13G)
Disclosed stakes, with their amendments. A filing is not always a purchase: there are also reductions and changes of filing entity.
This list may be incomplete: we hold 13D and 13G filings made since Dec 23, 2024. A holder above 5% that has not filed anything since then is not shown here.
- FMR4.6%(fell below 5%)13G · amendmentfiling ↗Event: Sep 30, 2026 · filed: Oct 7, 2026
- Venrock Healthcare Capital Partners III5.6%13Gfiling ↗Event: Sep 14, 2026 · filed: Sep 21, 2026
- Perceptive Advisors8.1%13G · amendmentfiling ↗Event: Jun 30, 2026 · filed: Aug 14, 2026
Above 5% over time (13D/13G)
Each holder with its filings in order. History since December 2024.
Flagged material events (8-K)
Unregistered sale of equity securities (Item 3.02)
«X4 Pharmaceuticals Secures Up to $150 Million Senior Debt Facility with K2 HealthVentures»
Change in directors or officers (Item 5.02)
«X4 Pharmaceuticals Appoints Kelly Gold, Experienced Chief Financial Officer, to its Board of Directors»
Change in directors or officers (Item 5.02)
Change in directors or officers (Item 5.02)
Alert items the company itself flagged in its 8-K filings with the SEC, most serious first. It is the form's label, with no interpretation from us: Item 5.02 covers routine appointments as well as a chief executive's departure; open the filing. The quoted headline is the original press release's.
All material events (8-K)
Earnings, agreements, financing, management changes and announcements from the last year, with a filter by type and a link to each filing.
Other Health Care stocks in managers' portfolios
Same sector and a similar number of concentrated managers holding them. It is a list to keep exploring, not a recommendation.
- Achieve Life SciencesACHV · 6 managers
- Artiva BiotherapeuticsARTV · 6 managers
- Anteris Technologies GlobalAVR · 5 managers
- Compass TherapeuticsCMPX · 5 managers
- Crinetics PharmaceuticalsCRNX · 5 managers
- IncyteINCY · 5 managers