RPID · Rapid Micro Biosystems, Inc. · Shareholders & Ownership

$0.77 0.00 (-0.25%) At close · Oct 20

Market Cap

$38.80M

50.16M

Volume · Oct 20 108.24K Avg daily vol (3M) 254.2K

Every disclosed holder of RPID in one list: 13F institutions, Schedule 13D and 13G filers, insiders (Forms 3, 4 and 5) and registered funds, each from its own latest filing. Holders nest by CIK and SEC reporting links, never by name, and each is summed once.

How the holder list picks a filing →

Who Owns RPID

13F quarter Sep 30, 2026, combined view: filers that have not filed yet carry their Jun 30, 2026 positions

Holder group	Holders	Shares	% Out	Summed
Institutional (13F)	36	17,772,474	35.43%	Yes
Insiders (Forms 3, 4, 5)	0	0	0.00%	No
13D/G-only blocks	3	8,433,600	16.81%	Yes
Remaining	—	23,953,482	47.75%	Rest
Registered funds (N-PORT, not summed)	14	1,352,725	2.70%	No

Shares outstanding: 50,159,556, the issuer's latest cover-page count restated onto today's split basis.

Insiders are listed but not summed: the issuer has more than one class of common stock and Forms 3, 4 and 5 report one issuer-wide balance across them.

13D/G-only counts each filer's latest 13D or 13G that no 13F report of the listing contains, that names no 13F filer and that no counted insider files. Funds are never summed: their shares sit inside their advisers' 13F reports.

Holders of RPID

One row per holder Every filing By ultimate parent

All 13F Funds Insiders 13D/G Non-US

#	Holder	Shares	% Out	Change	As of	Notes
1	Bain Capital Life Sciences Investors, LLC 13F CIK 1703031 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	8,434,560	16.82%	0	Jun 30, 2026	carried, not yet filed for the newest quarter
1.1	Bain Capital Life Sciences Investors, LLC Insider CIK 1703031 · May 20, 2026 10% Owner, issuer-wide, not summed	8,434,560	16.82%	0	May 20, 2026	10% Owner, issuer-wide, not summed
1.2	BCLS I Investco, LP 13G CIK 1687968 · Unknown · Jun 30, 2026 Rule 13d-1(d), exempt investor, not summed	7,651,369	15.25%	—	Jun 30, 2026	Rule 13d-1(d), exempt investor, not summed
2	Longitude Capital Partners II, LLC 13G CIK 1647491 · Unknown · Mar 31, 2026 Rule 13d-1(d), exempt investor	3,529,245	7.04%	—	Mar 31, 2026	Rule 13d-1(d), exempt investor
2.1	Longitude Capital Partners II, LLC Insider CIK 1647491 · Feb 4, 2026 10% Owner, issuer-wide, not summed	4,029,245	8.03%	—	Feb 4, 2026	10% Owner, issuer-wide, not summed
3	ARMISTICE CAPITAL, LLC 13F CIK 1601086 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	3,328,000	6.63%	+3,328,000	Jun 30, 2026	carried, not yet filed for the newest quarter
3.1	ARMISTICE CAPITAL, LLC 13G CIK 1601086 · Registered investment adviser · Jun 30, 2026 Rule 13d-1(b), qualified institution, not summed	3,328,000	6.63%	—	Jun 30, 2026	Rule 13d-1(b), qualified institution, not summed
4	Endeavour Medtech Growth II LP 13G CIK 1873032 · Unknown · Dec 31, 2025 Rule 13d-1(c), passive investor	2,257,099	4.50%	0	Dec 31, 2025	Rule 13d-1(c), passive investor
5	ABG-WTT Global Life Science Capital Partners GP Ltd 13F CIK 1832108 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	1,848,296	3.68%	0	Jun 30, 2026	carried, not yet filed for the newest quarter
6	Spignesi Robert G. Jr. Insider CIK 1853904 · Jul 22, 2026 Director, PRESIDENT AND CEO, issuer-wide, not summed	1,191,973	2.38%	+1,402	Jul 22, 2026	Director, PRESIDENT AND CEO, issuer-wide, not summed
6.1	SPIGNESI ROBERT G JR 13D CIK 1853904 · Mar 28, 2024	2,647,256	5.28%	—	Mar 28, 2024
7	VANGUARD CAPITAL MANAGEMENT LLC 13F CIK 2100119 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	982,034	1.96%	-460	Jun 30, 2026	carried, not yet filed for the newest quarter
8	VANGUARD TOTAL STOCK MARKET INDEX FUND Fund S000002848 · Registered fund · Jun 30, 2026 VANGUARD INDEX FUNDS, not summed	750,984	1.50%	0	Jun 30, 2026	VANGUARD INDEX FUNDS, not summed
9	WIRTJES SEAN M Insider CIK 1289733 · May 29, 2026 CHIEF FINANCIAL OFFICER, issuer-wide, not summed	568,981	1.13%	+12,787	May 29, 2026	CHIEF FINANCIAL OFFICER, issuer-wide, not summed
10	KHAZANAH NASIONAL BERHAD 13F CIK 1763068 · Jun 30, 2026 carried, not yet filed for the newest quarter	566,905	1.13%	0	Jun 30, 2026	carried, not yet filed for the newest quarter
11	Evernest Financial Advisors, LLC 13F CIK 2009530 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	506,000	1.01%	+73,490	Jun 30, 2026	carried, not yet filed for the newest quarter
12	Advent International, L.P. 13F CIK 1034196 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	379,794	0.76%	-172,583	Jun 30, 2026	carried, not yet filed for the newest quarter
13	Wilson John J. Addington Insider CIK 1872301 · Mar 11, 2026 CHIEF OPERATING OFFICER, issuer-wide, not summed	316,762	0.63%	-9,603	Mar 11, 2026	CHIEF OPERATING OFFICER, issuer-wide, not summed
14	MILLENNIUM MANAGEMENT LLC 13F CIK 1273087 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	236,599	0.47%	-46,681	Jun 30, 2026	carried, not yet filed for the newest quarter
15	GEODE CAPITAL MANAGEMENT, LLC 13F CIK 1214717 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	228,041	0.45%	-19,136	Jun 30, 2026	carried, not yet filed for the newest quarter
16	RENAISSANCE TECHNOLOGIES LLC 13F CIK 1037389 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	212,101	0.42%	+85,484	Jun 30, 2026	carried, not yet filed for the newest quarter
17	VANGUARD EXTENDED MARKET INDEX FUND Fund S000002841 · Registered fund · Jun 30, 2026 VANGUARD INDEX FUNDS, not summed	202,760	0.40%	-772	Jun 30, 2026	VANGUARD INDEX FUNDS, not summed
18	BlackRock, Inc. 13F CIK 2012383 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	189,832	0.38%	+32,600	Jun 30, 2026	carried, not yet filed for the newest quarter
18.1	iShares Micro-Cap ETF Fund S000004439 · Registered fund · Jun 30, 2026 iShares Trust, not summed	112,127	0.22%	+33,083	Jun 30, 2026	iShares Trust, not summed
19	Kollender Richard S Insider CIK 1415666 · Jul 24, 2026 Director, issuer-wide, not summed	133,826	0.27%	+3,508	Jul 24, 2026	Director, issuer-wide, not summed
20	Legato Capital Management LLC 13F CIK 1442641 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	119,534	0.24%	-155,390	Jun 30, 2026	carried, not yet filed for the newest quarter
21	VANGUARD FIDUCIARY TRUST CO 13F CIK 933478 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	110,484	0.22%	+772	Jun 30, 2026	carried, not yet filed for the newest quarter
22	Fidelity Extended Market Index Fund Fund S000006021 · Registered fund · May 31, 2026 Fidelity Concord Street Trust, not summed	107,845	0.22%	+7,480	May 31, 2026	Fidelity Concord Street Trust, not summed
23	DIMENSIONAL FUND ADVISORS LP 13F CIK 354204 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	104,192	0.21%	+16,603	Jun 30, 2026	carried, not yet filed for the newest quarter
23.1	Dimensional U.S. Small Cap ETF Fund S000070906 · Registered fund · Jul 31, 2026 Dimensional ETF Trust, not summed	30,705	0.06%	0	Jul 31, 2026	Dimensional ETF Trust, not summed
23.2	U.S. MICRO CAP PORTFOLIO Fund S000000948 · Registered fund · Jul 31, 2026 DFA INVESTMENT DIMENSIONS GROUP INC, not summed	14,363	0.03%	-7,324	Jul 31, 2026	DFA INVESTMENT DIMENSIONS GROUP INC, not summed
24	PEI MELINDA LITHERLAND Insider CIK 1703469 · May 29, 2026 Director, issuer-wide, not summed	100,687	0.20%	+12,787	May 29, 2026	Director, issuer-wide, not summed
25	STATE STREET CORP 13F CIK 93751 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	93,874	0.19%	0	Jun 30, 2026	carried, not yet filed for the newest quarter
26	XTX Topco Ltd 13F CIK 1828301 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	79,727	0.16%	+18,657	Jun 30, 2026	carried, not yet filed for the newest quarter
27	LOWENSTEIN INESE Insider CIK 1900476 · May 29, 2026 Director, issuer-wide, not summed	70,687	0.14%	+12,787	May 29, 2026	Director, issuer-wide, not summed
28	Malloy Kirk Insider CIK 1326794 · May 29, 2026 Director, issuer-wide, not summed	70,687	0.14%	+12,787	May 29, 2026	Director, issuer-wide, not summed
29	SEI INVESTMENTS CO 13F CIK 350894 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	66,869	0.13%	-217,947	Jun 30, 2026	carried, not yet filed for the newest quarter
30	NORTHERN TRUST CORP 13F CIK 73124 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	42,106	0.08%	-6,173	Jun 30, 2026	carried, not yet filed for the newest quarter
31	ALGERT GLOBAL LLC 13F CIK 1275218 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	38,307	0.08%	+15,126	Jun 30, 2026	carried, not yet filed for the newest quarter
32	FNY Investment Advisers, LLC 13F CIK 1742998 · Unknown · Sep 30, 2026	35,000	0.07%	+35,000	Sep 30, 2026
33	Fidelity Total Market Index Fund Fund S000006026 · Registered fund · May 31, 2026 Fidelity Concord Street Trust, not summed	31,525	0.06%	0	May 31, 2026	Fidelity Concord Street Trust, not summed
34	RICCIARDI NATALE S Insider CIK 1107158 · Feb 27, 2026 Director, issuer-wide, not summed	29,442	0.06%	+842	Feb 27, 2026	Director, issuer-wide, not summed
35	Fidelity Series Total Market Index Fund Fund S000065248 · Registered fund · May 31, 2026 Fidelity Concord Street Trust, not summed	28,726	0.06%	+1,631	May 31, 2026	Fidelity Concord Street Trust, not summed
36	MORGAN STANLEY 13F CIK 895421 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	27,587	0.06%	-1,620	Jun 30, 2026	carried, not yet filed for the newest quarter
37	Fidelity Nasdaq Composite Index Fund Fund S000055366 · Registered fund · May 31, 2026 Fidelity Concord Street Trust, not summed	26,152	0.05%	+4,630	May 31, 2026	Fidelity Concord Street Trust, not summed
38	JANE STREET GROUP, LLC 13F CIK 1595888 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	25,931	0.05%	-106,994	Jun 30, 2026	carried, not yet filed for the newest quarter
39	HRT FINANCIAL LP 13F CIK 1475597 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	23,093	0.05%	+23,093	Jun 30, 2026	carried, not yet filed for the newest quarter
40	Bika Dafni Insider CIK 2070373 · May 21, 2026 Director, issuer-wide, not summed	19,300	0.04%	—	May 21, 2026	Director, issuer-wide, not summed
41	CITADEL ADVISORS LLC 13F CIK 1423053 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	16,142	0.03%	+16,142	Jun 30, 2026	carried, not yet filed for the newest quarter
42	OSAIC HOLDINGS, INC. 13F CIK 1677044 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	14,300	0.03%	+300	Jun 30, 2026	carried, not yet filed for the newest quarter
43	VANGUARD BALANCED INDEX FUND Fund S000002560 · Registered fund · Jun 30, 2026 VANGUARD VALLEY FORGE FUNDS, not summed	14,205	0.03%	+312	Jun 30, 2026	VANGUARD VALLEY FORGE FUNDS, not summed
44	VANGUARD INSTITUTIONAL TOTAL STOCK MARKET INDEX FUND Fund S000002855 · Registered fund · Jun 30, 2026 VANGUARD INSTITUTIONAL INDEX FUNDS, not summed	14,085	0.03%	0	Jun 30, 2026	VANGUARD INSTITUTIONAL INDEX FUNDS, not summed
45	NANO CAP NEW MILLENNIUM GROWTH FUND L P 13F CIK 1277890 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	12,500	0.02%	0	Jun 30, 2026	carried, not yet filed for the newest quarter
46	AMERICAN CENTURY COMPANIES INC 13F CIK 748054 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	11,638	0.02%	-5,284	Jun 30, 2026	carried, not yet filed for the newest quarter
47	Avantis U.S. Small Cap Equity ETF Fund S000074835 · Registered fund · May 31, 2026 American Century ETF Trust, not summed	11,638	0.02%	-5,284	May 31, 2026	American Century ETF Trust, not summed
48	Vanguard Global Advisers, LLC 13F CIK 1811242 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	11,630	0.02%	0	Jun 30, 2026	carried, not yet filed for the newest quarter
49	Wealth Analytics Partners, LLC 13F CIK 2110717 · Unknown · Sep 30, 2026	10,000	0.02%	+10,000	Sep 30, 2026
50	Larson Financial Group LLC 13F CIK 1731061 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	8,395	0.02%	+2,904	Jun 30, 2026	carried, not yet filed for the newest quarter

Shares are restated onto today's split basis. Change compares each row with the same holder's previous filing in the same source; a dash means there is none to compare. Nested 13D/G, insider and fund rows are not summed, since a 13F report already holds them.

Showing 1–50 of 58 holders

Create a free account to page through every holder, filter by source and group by ultimate parent.

Key facts CIK 1380106 CUSIP 75340L104 13F (30d) 21 filings 4 filers Visit website Investor relations