Phathom Pharmaceuticals, Inc.

PHAT

Exchange: Nasdaq
Industry: Pharmaceutical Preparations
SEC CIK: 0001783183

SEC filings (opens in a new tab)

No open-market purchases or sales by Phathom Pharmaceuticals, Inc. insiders were filed in the last 90 days; 161 institutions reported holding it in 13F filings for Q2 2026, worth $782.1M in total; no superinvestor holds it.

Q1 2026 vs. Q4 2025

How the institutions holding Phathom Pharmaceuticals, Inc. changed between Q4 2025 and Q1 2026.

All holders in Q1 2026 All holders in Q4 2025

13F holders of PHAT: Q4 2025 compared with Q1 2026
Measure	Q4 2025	Of which not filed for Q1 2026	Q1 2026	Change
Holders	173	1	174	+2
Shares	62.0M	3.18M	68.9M	+10.1M (+17.2%)
Value	$1.03B	$52.7M	$765.5M	−$207.3M (−21.3%)

1 institution that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so the changes leave them out.

New holders (37)

Institutions that held Phathom Pharmaceuticals, Inc. at the end of Q1 2026 but not at the end of Q4 2025.

Institutions new to PHAT in Q1 2026
Institution	Shares	Value	% of portfolio
Vanguard Capital Management LLC	2,583,636	$28.7M	0.00%
Nomura Asset Management International Inc.	1,205,369	$13.4M	0.02%
Franklin Resources Inc	994,504	$11.0M	0.00%
Perceptive Advisors LLC	925,000	$10.3M	0.20%
Marshall Wace, LLP	860,692	$9.56M	0.01%
Vanguard Portfolio Management LLC	666,029	$7.40M	0.00%
EcoR1 Capital, LLC	625,000	$6.94M	0.30%
Vanguard Fiduciary Trust Co	338,713	$3.76M	0.00%
Renaissance Technologies LLC	305,800	$3.40M	0.01%
Squarepoint Ops LLC	275,161	$3.06M	0.01%
Freestone Grove Partners LP	84,573	$939.6K	0.01%
KBC Group NV	77,139	$857.0K	0.00%
Burkehill Global Management, LP	75,000	$833.3K	0.04%
Diadema Partners LP	54,650	$607.2K	0.25%
Stonepine Capital Management, LLC	50,010	$555.6K	0.49%
Aquatic Capital Management LLC	40,852	$453.9K	0.01%
Algert Global LLC	39,420	$438.0K	0.01%
Allstate Corp	32,687	$363.2K	0.00%
Man Group plc	30,352	$337.2K	0.00%
Vanguard Asset Management, Ltd	28,506	$316.7K	0.00%
Vanguard Global Advisers, LLC	26,511	$294.5K	0.00%
LPL Financial LLC	17,207	$191.2K	0.00%
State of New Jersey Common Pension Fund D	15,997	$177.7K	0.00%
DRW Securities, LLC	15,921	$176.9K	0.01%
Lazard Asset Management LLC	14,671	$163.0K	0.00%
Dynamic Technology Lab Private Ltd	12,111	$134.6K	0.02%
Quadrature Capital Ltd	12,078	$134.2K	0.00%
Quantinno Capital Management LP	11,536	$128.2K	0.00%
Primoris Wealth Advisors, LLC	11,449	$127.2K	0.09%
Vanguard Investments Australia, Ltd.	11,276	$125.3K	0.00%
State of Wyoming	4,936	$54.8K	0.01%
Clear Street Markets LLC	3,048	$33.9K	0.02%
Truvestments Capital LLC	225	$2.50K	0.00%
MAI Capital Management	23	$256	0.00%
Root Financial Partners, LLC	11	$122	0.00%
Stone House Investment Management, LLC	8	$89	0.00%
Hughes Financial Services, LLC	1	$11	0.00%

Sold out (35)

Institutions that held Phathom Pharmaceuticals, Inc. at the end of Q4 2025 and filed for Q1 2026 without it.

Institutions that sold out of PHAT in Q1 2026
Institution	Shares, Q4 2025	Value, Q4 2025
Divisadero Street Capital Management, LP	662,312	$11.0M
Moore Capital Management, LP	600,000	$9.95M
Next Century Growth Investors LLC	393,774	$6.53M
Jane Street Group, LLC	384,770	$6.38M
Caxton Associates LLP	181,968	$3.02M
Southeast Asset Advisors Inc.	42,874	$711.3K
Y-Intercept (Hong Kong) Ltd	30,488	$505.8K
Occidental Asset Management, LLC	29,919	$496.4K
Quest Partners LLC	28,250	$468.7K
HRT Financial LP	27,010	$448.0K
Acadian Asset Management LLC	22,185	$367.0K
Fox Run Management, L.L.C.	20,487	$339.9K
SG Americas Securities, LLC	16,497	$274.0K
Virtu Financial LLC	15,540	$258.0K
Baader Bank INC	15,000	$248.8K
Rafferty Asset Management, LLC	13,855	$229.9K
Scientech Research LLC	12,879	$213.7K
Graham Capital Management, L.P.	12,867	$213.5K
Susquehanna Fundamental Investments, LLC	11,473	$190.3K
Entropy Technologies, LP	11,000	$182.5K
Axq Capital, LP	10,540	$174.9K
9823 Capital, L.P.	10,429	$173.0K
Canada Pension Plan Investment Board	4,600	$76.3K
RiverPark Advisors, LLC	2,807	$46.6K
Kestra Advisory Services, LLC	2,275	$37.7K
Simplex Trading, LLC	1,599	$26.5K
Amalgamated Bank	1,248	$21.0K
Federated Hermes, Inc.	549	$9.11K
Quantbot Technologies LP	535	$8.88K
MCF Advisors LLC	446	$7.40K
Daiwa Securities Group Inc.	260	$4.00K
Fortitude Family Office, LLC	208	$3.45K
Caitong International Asset Management Co., Ltd	28	$465
SRS Capital Advisors, Inc.	6	$100
Essential Partners LLC	6	$100

Not filed for Q1 2026 yet (1)

Institutions that held Phathom Pharmaceuticals, Inc. at the end of Q4 2025 and haven't filed a 13F for Q1 2026. Not filing isn't selling, so they aren't counted as sold out.

Institutions holding PHAT in Q4 2025 that haven't filed for Q1 2026
Institution	Shares, Q4 2025	Value, Q4 2025
Vanguard Group Inc	3,177,211	$52.7M