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Livermore
Livermore
ZHEN

X4 Pharmaceuticals, Inc

XFOR
Exchange
Nasdaq
Industry
Biological Products, (No Diagnostic Substances)
SEC CIK
0001501697

In the last 90 days, X4 Pharmaceuticals, Inc insiders filed 0 open-market purchases and 3 sales; 89 institutions reported holding it in 13F filings for Q2 2026, worth $463.0M in total; no superinvestor holds it.

Holders of 5% or more of XFOR

Holders whose latest Schedule 13D or 13G filing reports 5% or more of X4 Pharmaceuticals, Inc, largest stake first. The change is against the holder's previous filing.

Holders of 5% or more of XFOR
HolderLatest formStakeChangeFirst filedLatest filingFiling
FMR LLC13G14.80%8.50M sharesNewNov 7, 20251 filingNov 7, 2025SEC
Empery Asset Management, LP13G9.99%2.50M sharesNewOct 21, 20251 filingOct 21, 2025SEC
Coastlands Capital LP13G9.99%2.49M shares0.00 ppfrom 9.99%Aug 18, 20252 filingsOct 3, 2025SEC
Bain Capital Life Sciences Fund, L.P.13G9.99%2.44M shares0.00 ppfrom 9.99%Aug 13, 20252 filingsSep 15, 2025SEC
Deep Track Capital, LP13G9.99%2.37M sharesNewAug 19, 20251 filingAug 19, 2025SEC
Nantahala Capital Management, LLC13G9.99%2.24M sharesNewNov 14, 20251 filingNov 14, 2025SEC
Trails Edge Capital Partners, LP13G9.90%2.32M sharesNewAug 18, 20251 filingAug 18, 2025SEC
Biotechnology Value Fund L P13G9.90%2.24M sharesNewAug 20, 20251 filingAug 20, 2025SEC
Perceptive Advisors LLC13G7.60%6.06M sharesNewNov 3, 20251 filingNov 3, 2025SEC
Growth Equity Opportunities 18 VGE, LLC13D/A6.20%5.06M shares−3.79 ppfrom 9.99%Aug 15, 20252 filingsOct 29, 2025SEC

Stakes are as of each holder's latest filing. Holders whose last filing was in the old format (before December 18, 2024) have no stake on record and are not listed, and after an acquisition or delisting holders usually stop filing.

13D and 13G filings

16 Schedule 13D and 13G filings on X4 Pharmaceuticals, Inc, newest first, including old-format filings without a stake.

Schedule 13D and 13G filings on XFOR
Filed (ET)FilerFormStakeChangeEvent dateFiling
Nov 14, 20254:39 PM ETNantahala Capital Management, LLCand 2 others13G9.99%2.24M sharesNewSep 30, 2025SEC
Nov 7, 202511:13 AM ETFMR LLCand 1 other13G14.80%8.50M sharesNewOct 31, 2025SEC
Nov 3, 20254:09 PM ETPerceptive Advisors LLCand 2 others13G7.60%6.06M sharesNewOct 27, 2025SEC
Oct 29, 20256:04 PM ETGrowth Equity Opportunities 18 VGE, LLCand 11 others13D/A6.20%5.06M shares−3.79 ppfrom 9.99%Oct 27, 2025SEC
Oct 21, 20259:00 AM ETEmpery Asset Management, LPand 2 others13G9.99%2.50M sharesNewSep 30, 2025SEC
Oct 3, 20255:25 PM ETCoastlands Capital LPand 4 others13G9.99%2.49M shares0.00 ppfrom 9.99%Oct 3, 2025SEC
Sep 15, 20254:30 PM ETBain Capital Life Sciences Fund, L.P.and 5 others13G9.99%2.44M shares0.00 ppfrom 9.99%Sep 9, 2025SEC
Aug 20, 20255:41 PM ETBiotechnology Value Fund L Pand 9 others13G9.90%2.24M sharesNewAug 13, 2025SEC
Aug 19, 20254:05 PM ETDeep Track Capital, LPand 2 others13G9.99%2.37M sharesNewAug 12, 2025SEC
Aug 18, 20255:00 PM ETTrails Edge Capital Partners, LPand 2 others13G9.90%2.32M sharesNewAug 11, 2025SEC
Aug 18, 20254:26 PM ETCoastlands Capital LPand 4 others13D9.99%2.48M sharesNewAug 11, 2025SEC
Aug 15, 20254:54 PM ETGrowth Equity Opportunities 18 VGE, LLCand 11 others13D/A9.99%2.24M shares–Aug 13, 2025SEC
Aug 14, 20255:53 PM ETOrbiMed Advisors LLC13G/A1.70%134.9K shares–Below 5%Jun 30, 2025SEC
Aug 13, 20259:40 PM ETBain Capital Life Sciences Fund, L.P.and 4 others13D9.99%2.44M sharesNewAug 11, 2025SEC
Jul 18, 202511:48 AM ETBlackRock, Inc.13G/A3.00%179.1K shares–Below 5%Jun 30, 2025SEC
Jan 31, 202510:09 AM ETVanguard Group Inc13G/A4.80%8.20M shares–Below 5%Dec 31, 2024SEC

Form 144: proposed insider sales

Notices from officers, directors and other affiliates planning to sell X4 Pharmaceuticals, Inc shares.

No Form 144 notices for X4 Pharmaceuticals, Inc are on file.