Institutional HoldersBeta

Who holds a company, from every 13F filed for the quarter, one row per filer exactly as filed, against the latest share count the company reported.

Kalaris Therapeutics, Inc.

CIK 0001754068KLRS· quarter ending 2026-06-30

Shares outstanding

23,804,981

as of 2026-08-04 · 10-Q cover page, filed 2026-08-11

Held by 13F filers

18,030,981

75.7% of shares outstanding

Holders

-2 vs 2026-03-31 · 9 new, 11 exited

Value

$73.4M

shares -3.7% vs prior quarter

Share classes (cover page of the 10-Q filed 2026-08-11, as of 2026-08-04)

Class	Listed	Shares outstanding	Held by 13F filers	% of class	Holders	CUSIP
Common stock	KLRS · NASDAQ	23,804,981	18,030,981	75.7%	56	482929106

Each class is compared with its own share count; classes are not added together. A class that is not exchange-listed cannot be held by 13F filers.

Securities (CUSIPs held in 13F this quarter)

tick to combine

Count	CUSIP	Class (as filers write it)	Holders	Shares held	Class shares	% of class	Value	Options	Mapped via
	482929106	COM	56	18,030,981	23,804,981	75.7%	$73.4M	—	13DG	holders →

Totals combine the ticked CUSIPs and update as you tick: common-stock classes by default; preferreds, notes, warrants and depositary shares are listed but not counted. "holders →" shows a single CUSIP on its own. Bonds are held as a principal amount, not shares. Options positions are never counted as holdings. 2 further CUSIPs map to this company (mostly bonds) but no 13F filer held them this quarter.

Top holders (56 of 56 · 482929106)

change vs 2026-03-31

#	Filer	Shares	% of class	Value	Change
1	SAMSARA BIOCAPITAL, LLC	12,881,175	54.11%	$52.4M	-66,906 (-0.5%)
2	RTW INVESTMENTS, LP	1,300,000	5.46%	$5.3M	—
3	Alyeska Investment Group, L.P.	572,687	2.41%	$2.3M	—
4	Siren, L.L.C.	435,798	1.83%	$1.8M	—
5	VANGUARD CAPITAL MANAGEMENT LLC	398,712	1.67%	$1.6M	+143,364 (+56.1%)
6	Ikarian Capital, LLC	360,000	1.51%	$1.5M	—
7	UBS Group AG	262,131	1.10%	$1.1M	+255,947 (+4138.9%)
8	RENAISSANCE TECHNOLOGIES LLC	149,351	0.63%	$608K	+83,200 (+125.8%)
9	MARSHALL WACE, LLP	139,201	0.58%	$567K	+71,322 (+105.1%)
10	GEODE CAPITAL MANAGEMENT, LLC	114,037	0.48%	$464K	+26,492 (+30.3%)
11	Woodline Partners LP	100,000	0.42%	$407K	—
12	ADAR1 Capital Management, LLC	100,000	0.42%	$407K	—
13	WHI TRUST Co LLC	97,493	0.41%	$397K	—
14	RAYMOND JAMES FINANCIAL INC	97,164	0.41%	$395K	-21,723 (-18.3%)
15	CITADEL ADVISORS LLC	95,772	0.40%	$390K	NEW
16	BOOTHBAY FUND MANAGEMENT, LLC	92,261	0.39%	$376K	—
17	Verdad Advisers, LP	80,297	0.34%	$327K	NEW
18	MORGAN STANLEY	72,326	0.30%	$294K	+33,982 (+88.6%)
19	VANGUARD FIDUCIARY TRUST CO	66,179	0.28%	$269K	+29,462 (+80.2%)
20	BlackRock, Inc.	54,442	0.23%	$222K	+18,399 (+51.0%)
21	Fortis Capital Advisors, LLC	40,000	0.17%	$163K	—
22	Belpointe Asset Management LLC	40,000	0.17%	$163K	—
23	Pale Fire Capital SE	39,626	0.17%	$161K	NEW
24	Squarepoint Ops LLC	38,775	0.16%	$158K	-998 (-2.5%)
25	BRIDGEWAY CAPITAL MANAGEMENT, LLC	32,500	0.14%	$132K	+10,000 (+44.4%)
26	Stonepine Capital Management, LLC	30,122	0.13%	$123K	+9,722 (+47.7%)
27	Connor, Clark & Lunn Investment Management Ltd.	30,007	0.13%	$122K	+16,352 (+119.8%)
28	Trexquant Investment LP	29,737	0.12%	$121K	NEW
29	STATE STREET CORP	26,510	0.11%	$108K	—
30	NORTHERN TRUST CORP	25,839	0.11%	$105K	+11,390 (+78.8%)
31	Velan Capital Investment Management LP	25,000	0.11%	$102K	+7,000 (+38.9%)
32	TWO SIGMA INVESTMENTS, LP	23,847	0.10%	$97K	-6,803 (-22.2%)
33	WealthTrust Asset Management, LLC	20,416	0.09%	$83K	+8,000 (+64.4%)
34	Independent Advisor Alliance	18,125	0.08%	$74K	+3,895 (+27.4%)
35	RBF Capital, LLC	17,391	0.07%	$71K	—
36	Quadrature Capital Ltd	16,527	0.07%	$67K	NEW
37	GOLDMAN SACHS GROUP INC	16,054	0.07%	$65K	-94,449 (-85.5%)
38	DIMENSIONAL FUND ADVISORS LP	15,958	0.07%	$65K	NEW
39	SUSQUEHANNA INTERNATIONAL GROUP, LLP	14,221	0.06%	$58K	-38,463 (-73.0%)
40	HRT FINANCIAL LP	13,723	0.06%	$55K	+2,106 (+18.1%)
41	NANO CAP NEW MILLENNIUM GROWTH FUND L P	12,500	0.05%	$51K	+8,500 (+212.5%)
42	Virtu Financial LLC	10,845	0.05%	$44K	NEW
43	Sigma Planning Corp	10,167	0.04%	$41K	NEW
44	FMR LLC	7,806	0.03%	$32K	—
45	Tower Research Capital LLC (TRC)	2,560	0.01%	$10K	+2,421 (+1741.7%)
46	Steward Partners Investment Advisory, LLC	2,215	0.01%	$9K	—
47	Vanguard Global Advisers, LLC	725	0.00%	$3K	—
48	BARCLAYS PLC	303	0.00%	$1K	-4,977 (-94.3%)
49	Strengthening Families & Communities, LLC	268	0.00%	$1K	—
50	BNP PARIBAS FINANCIAL MARKETS	52	0.00%	$212	-600 (-92.0%)
51	JPMORGAN CHASE & CO	50	0.00%	$211	—
52	Parallel Advisors, LLC	49	0.00%	$199	—
53	HARBOUR INVESTMENTS, INC.	13	0.00%	$53	—
54	ROYAL BANK OF CANADA	12	0.00%	$0	-91 (-88.3%)
55	Caitong International Asset Management Co., Ltd	7	0.00%	$28	NEW
56	SBI Securities Co., Ltd.	5	0.00%	$20	—

Exited since 2026-03-31 (11 filers; largest 11 shown)

Paradigm Biocapital Advisors LP	−700,000
Propel Bio Management, LLC	−295,771
Kalehua Capital Management LLC	−271,170
Simplify Asset Management Inc.	−87,426
MILLENNIUM MANAGEMENT LLC	−59,534
683 Capital Management, LLC	−45,000
Qube Research & Technologies Ltd	−11,103
Johnson Financial Group, Inc.	−10,000
CITIGROUP INC	−8,703
Fortitude Family Office, LLC	−114
FEDERATED HERMES, INC.	−34

Large holders from 13D/13G (latest per reporting person, last 2 years)

Filed when a holder crosses 5% or changes materially, so often more current than the quarter-end 13F. Percentages are the filer's own, against the share count they used.

Reporting person	Form	Filed	Event	Shares	% of class
Samsara BioCapital GP, LLC	SCHEDULE 13D/A	2026-05-22	2026-05-20	10,671,965	44.9%
Srinivas Akkaraju	SCHEDULE 13D/A	2026-05-22	2026-05-20	12,900,583	54.2%
Samsara Opportunity Fund, L.P.	SCHEDULE 13D/A	2026-05-22	2026-05-20	2,224,147	9.3%
Samsara Opportunity Fund GP, LLC	SCHEDULE 13D/A	2026-05-22	2026-05-20	2,224,147	9.3%
Samsara BioCapital, L.P.	SCHEDULE 13D/A	2026-05-22	2026-05-20	10,657,028	44.8%
Roderick Wong	SCHEDULE 13G	2026-02-17	2025-12-31	1,300,000	5.7%
RTW Investments, LP	SCHEDULE 13G	2026-02-17	2025-12-31	1,300,000	5.7%
Raymond Debbane	SCHEDULE 13G/A	2025-07-29	2025-06-30	282,586	1.5%
Invus Public Equities, L.P.	SCHEDULE 13G/A	2025-07-29	2025-06-30	282,586	1.5%
Invus Public Equities Advisors, LLC	SCHEDULE 13G/A	2025-07-29	2025-06-30	282,586	1.5%
Invus Global Management, LLC	SCHEDULE 13G/A	2025-07-29	2025-06-30	282,586	1.5%
Siren, L.L.C.	SCHEDULE 13G/A	2025-07-29	2025-06-30	282,586	1.5%
Oleg Nodelman	SCHEDULE 13G/A	2025-05-15	2025-03-31	201,718	1.1%
EcoR1 Capital Fund Qualified, L.P.	SCHEDULE 13G/A	2025-05-15	2025-03-31	191,242	1%
EcoR1 Capital, LLC	SCHEDULE 13G/A	2025-05-15	2025-03-31	201,718	1.1%
GILEAD SCIENCES, INC.	SCHEDULE 13G/A	2025-03-20	2025-03-18	723,273	3.9%

Source: SEC Form 13F-HR information tables for the quarter ending 2026-06-30 (filed within 45 days of quarter end; amendments applied; values normalised to dollars), the share count from the company's latest 10-K/10-Q XBRL cover page, and Schedule 13D/13G filings. Each row is a legal 13F filer as filed — related entities (e.g. Vanguard's advisers) are not merged. Retail brokerage accounts are not reported on 13F, so the remainder is mostly retail and insiders.