OSS · One Stop Systems, Inc. · Shareholders & Ownership

$5.91 +0.00 (+0.00%) At close · Oct 23

Russell 2000 member Rebalance outlook locked

Market Cap

$147.40M

24.94M

Volume · Oct 23 557.8K Avg daily vol (3M) 865.3K

Every disclosed holder of OSS 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 OSS

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)	109	10,593,769	42.48%	Yes
Insiders (Forms 3, 4, 5)	7	1,385,975	5.56%	Yes
13D/G-only blocks	2	1,117,343	4.48%	Yes
Remaining	—	11,843,043	47.49%	Rest
Registered funds (N-PORT, not summed)	78	2,847,920	11.42%	No

Shares outstanding: 24,940,130, the issuer's latest cover-page count restated onto today's split basis.

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 OSS

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	BlackRock, Inc. 13F CIK 2012383 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	1,837,840	7.37%	+1,240,537	Jun 30, 2026	carried, not yet filed for the newest quarter
1.1	BlackRock, Inc. 13G CIK 2012383 · Holding company · Jun 30, 2026 Rule 13d-1(b), qualified institution, not summed	1,833,734	7.35%	—	Jun 30, 2026	Rule 13d-1(b), qualified institution, not summed
1.2	iShares Russell 2000 ETF Fund S000004344 · Registered fund · Jun 30, 2026 iShares Trust, not summed	577,041	2.31%	—	Jun 30, 2026	iShares Trust, not summed
1.3	iShares Russell 2000 Growth ETF Fund S000004343 · Registered fund · Jun 30, 2026 iShares Trust, not summed	211,025	0.85%	—	Jun 30, 2026	iShares Trust, not summed
1.4	iShares Micro-Cap ETF Fund S000004439 · Registered fund · Jun 30, 2026 iShares Trust, not summed	74,788	0.30%	+22,865	Jun 30, 2026	iShares Trust, not summed
1.5	Master Small Cap Index Series Fund S000002716 · Registered fund · Jun 30, 2026 Quantitative Master Series LLC, not summed	42,003	0.17%	—	Jun 30, 2026	Quantitative Master Series LLC, not summed
2	JANE STREET GROUP, LLC 13F CIK 1595888 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	1,309,455	5.25%	+434,897	Jun 30, 2026	carried, not yet filed for the newest quarter
3	VANGUARD CAPITAL MANAGEMENT LLC 13F CIK 2100119 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	974,568	3.91%	+14,980	Jun 30, 2026	carried, not yet filed for the newest quarter
4	Horton Capital Partners Fund, LP 13D CIK 1567994 · Unknown · Jun 4, 2025	917,343	3.68%	-257,556	Jun 4, 2025
5	VANGUARD TOTAL STOCK MARKET INDEX FUND Fund S000002848 · Registered fund · Jun 30, 2026 VANGUARD INDEX FUNDS, not summed	693,556	2.78%	0	Jun 30, 2026	VANGUARD INDEX FUNDS, not summed
6	KNOWLES MICHAEL Insider CIK 1755059 · Aug 15, 2026 Director, Chief Executive Officer, issuer-wide	590,141	2.37%	-17,242	Aug 15, 2026	Director, Chief Executive Officer, issuer-wide
7	GEODE CAPITAL MANAGEMENT, LLC 13F CIK 1214717 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	572,918	2.30%	+320,465	Jun 30, 2026	carried, not yet filed for the newest quarter
8	BARD ASSOCIATES INC 13F CIK 1105907 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	526,370	2.11%	-14,296	Jun 30, 2026	carried, not yet filed for the newest quarter
9	Palisades Investment Partners, LLC 13F CIK 1427373 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	414,392	1.66%	+414,392	Jun 30, 2026	carried, not yet filed for the newest quarter
10	RENAISSANCE TECHNOLOGIES LLC 13F CIK 1037389 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	407,860	1.64%	+147,900	Jun 30, 2026	carried, not yet filed for the newest quarter
11	STATE STREET CORP 13F CIK 93751 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	384,259	1.54%	+282,583	Jun 30, 2026	carried, not yet filed for the newest quarter
11.1	STATE STREET SMALL/MID CAP EQUITY INDEX PORTFOLIO Fund S000050332 · Registered fund · Jun 30, 2026 STATE STREET INSTITUTIONAL INVESTMENT TRUST, not summed	5,800	0.02%	—	Jun 30, 2026	STATE STREET INSTITUTIONAL INVESTMENT TRUST, not summed
11.2	State Street Total Return V.I.S. Fund Fund S000001637 · Registered fund · Jun 30, 2026 STATE STREET VARIABLE INSURANCE SERIES FUNDS INC, not summed	567	0.00%	—	Jun 30, 2026	STATE STREET VARIABLE INSURANCE SERIES FUNDS INC, not summed
12	Ison James Insider CIK 1729652 · Feb 15, 2026 CPO, issuer-wide	373,055	1.50%	+32,860	Feb 15, 2026	CPO, issuer-wide
13	MILLENNIUM MANAGEMENT LLC 13F CIK 1273087 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	337,710	1.35%	-63,019	Jun 30, 2026	carried, not yet filed for the newest quarter
14	Qube Research & Technologies Ltd 13F CIK 1729829 · Exempt reporting adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	318,919	1.28%	+318,919	Jun 30, 2026	carried, not yet filed for the newest quarter
15	VANGUARD EXTENDED MARKET INDEX FUND Fund S000002841 · Registered fund · Jun 30, 2026 VANGUARD INDEX FUNDS, not summed	257,191	1.03%	+16,553	Jun 30, 2026	VANGUARD INDEX FUNDS, not summed
16	Galkin Vladimir 13G CIK 2020621 · Unknown · Oct 7, 2026 Rule 13d-1(c), passive investor	200,000	0.80%	-1,300,000	Oct 7, 2026	Rule 13d-1(c), passive investor
17	NORTHERN TRUST CORP 13F CIK 73124 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	178,101	0.71%	+131,127	Jun 30, 2026	carried, not yet filed for the newest quarter
17.1	Small Cap Index Fund Fund S000001245 · Registered fund · Jun 30, 2026 Northern Funds, not summed	10,996	0.04%	—	Jun 30, 2026	Northern Funds, not summed
18	TWO SIGMA INVESTMENTS, LP 13F CIK 1179392 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	162,193	0.65%	+162,193	Jun 30, 2026	carried, not yet filed for the newest quarter
19	VANGUARD FIDUCIARY TRUST CO 13F CIK 933478 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	157,365	0.63%	+28,606	Jun 30, 2026	carried, not yet filed for the newest quarter
20	VANGUARD PORTFOLIO MANAGEMENT LLC 13F CIK 2100121 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	155,408	0.62%	+155,408	Jun 30, 2026	carried, not yet filed for the newest quarter
21	Gabel Daniel G. Insider CIK 2044400 · Aug 7, 2026 Chief Financial Officer, issuer-wide	150,064	0.60%	-3,832	Aug 7, 2026	Chief Financial Officer, issuer-wide
22	Cambridge Investment Research Advisors, Inc. 13F CIK 1419186 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	149,292	0.60%	+3,668	Jun 30, 2026	carried, not yet filed for the newest quarter
23	NEW YORK STATE COMMON RETIREMENT FUND 13F CIK 810265 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	147,343	0.59%	+147,343	Jun 30, 2026	carried, not yet filed for the newest quarter
24	DIMENSIONAL FUND ADVISORS LP 13F CIK 354204 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	146,871	0.59%	+146,871	Jun 30, 2026	carried, not yet filed for the newest quarter
24.1	Dimensional U.S. Small Cap ETF Fund S000070906 · Registered fund · Jul 31, 2026 Dimensional ETF Trust, not summed	45,816	0.18%	—	Jul 31, 2026	Dimensional ETF Trust, not summed
24.2	U.S. SMALL CAP PORTFOLIO Fund S000000971 · Registered fund · Jul 31, 2026 DFA INVESTMENT DIMENSIONS GROUP INC, not summed	36,302	0.15%	—	Jul 31, 2026	DFA INVESTMENT DIMENSIONS GROUP INC, not summed
24.3	Dimensional U.S. Core Equity 2 ETF Fund S000070903 · Registered fund · Jul 31, 2026 Dimensional ETF Trust, not summed	22,586	0.09%	—	Jul 31, 2026	Dimensional ETF Trust, not summed
24.4	U.S. MICRO CAP PORTFOLIO Fund S000000948 · Registered fund · Jul 31, 2026 DFA INVESTMENT DIMENSIONS GROUP INC, not summed	12,335	0.05%	+11,611	Jul 31, 2026	DFA INVESTMENT DIMENSIONS GROUP INC, not summed
24.5	U.S. CORE EQUITY 1 PORTFOLIO Fund S000000979 · Registered fund · Jul 31, 2026 DFA INVESTMENT DIMENSIONS GROUP INC, not summed	6,664	0.03%	—	Jul 31, 2026	DFA INVESTMENT DIMENSIONS GROUP INC, not summed
25	Squarepoint Ops LLC 13F CIK 1642575 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	131,346	0.53%	+72,870	Jun 30, 2026	carried, not yet filed for the newest quarter
26	Informed Momentum Co LLC 13F CIK 1510989 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	130,568	0.52%	-5,421	Jun 30, 2026	carried, not yet filed for the newest quarter
27	Dumont Michael J. Insider CIK 1994330 · May 20, 2026 Director, issuer-wide	119,833	0.48%	+11,984	May 20, 2026	Director, issuer-wide
28	DNB Asset Management AS 13F CIK 1456670 · Investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	118,759	0.48%	-133,974	Jun 30, 2026	carried, not yet filed for the newest quarter
29	MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 13F CIK 1705339 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	99,272	0.40%	+25,407	Jun 30, 2026	carried, not yet filed for the newest quarter
29.1	Global X Russell 2000 ETF Fund S000085029 · Registered fund · Jul 31, 2026 GLOBAL X FUNDS, not summed	10,679	0.04%	—	Jul 31, 2026	GLOBAL X FUNDS, not summed
30	Trexquant Investment LP 13F CIK 1633445 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	98,442	0.39%	-119,387	Jun 30, 2026	carried, not yet filed for the newest quarter
31	MORGAN STANLEY 13F CIK 895421 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	88,902	0.36%	-343,017	Jun 30, 2026	carried, not yet filed for the newest quarter
32	OSAIC HOLDINGS, INC. 13F CIK 1677044 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	86,513	0.35%	+84,886	Jun 30, 2026	carried, not yet filed for the newest quarter
33	SEI INVESTMENTS CO 13F CIK 350894 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	84,393	0.34%	-82,239	Jun 30, 2026	carried, not yet filed for the newest quarter
34	Matz Gregory W Insider CIK 1536574 · May 26, 2026 Director, issuer-wide	78,914	0.32%	+3,984	May 26, 2026	Director, issuer-wide
35	GOLDMAN SACHS GROUP INC 13F CIK 886982 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	75,306	0.30%	-1,730	Jun 30, 2026	carried, not yet filed for the newest quarter
35.1	Goldman Sachs Small Cap Equity Insights Fund Fund S000009329 · Registered fund · Jul 31, 2026 Goldman Sachs Trust, not summed	35,029	0.14%	—	Jul 31, 2026	Goldman Sachs Trust, not summed
35.2	Goldman Sachs Small Cap Growth Insights Fund Fund S000014930 · Registered fund · Jul 31, 2026 Goldman Sachs Trust, not summed	16,746	0.07%	—	Jul 31, 2026	Goldman Sachs Trust, not summed
35.3	Goldman Sachs Absolute Return Tracker Fund Fund S000020314 · Registered fund · Aug 31, 2026 GOLDMAN SACHS TRUST, not summed	5,504	0.02%	—	Aug 31, 2026	GOLDMAN SACHS TRUST, not summed
35.4	Goldman Sachs Variable Insurance Trust Small Cap Equity Insights Fund Fund S000009355 · Registered fund · Jun 30, 2026 Goldman Sachs Variable Insurance Trust, not summed	2,703	0.01%	—	Jun 30, 2026	Goldman Sachs Variable Insurance Trust, not summed
36	Eddie Patel Inc 13F CIK 2078760 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	72,895	0.29%	+5,836	Jun 30, 2026	carried, not yet filed for the newest quarter
37	UBS Group AG 13F CIK 1610520 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	72,184	0.29%	-334,830	Jun 30, 2026	carried, not yet filed for the newest quarter
38	CITADEL ADVISORS LLC 13F CIK 1423053 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	71,202	0.29%	-285,474	Jun 30, 2026	carried, not yet filed for the newest quarter
39	Russell Investments Group, Ltd. 13F CIK 1692234 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	66,596	0.27%	+66,596	Jun 30, 2026	carried, not yet filed for the newest quarter
39.1	U.S. Small Cap Equity Fund Fund S000006864 · Registered fund · Jun 30, 2026 RUSSELL INVESTMENT FUNDS, not summed	4,780	0.02%	—	Jun 30, 2026	RUSSELL INVESTMENT FUNDS, not summed
40	CHARLES SCHWAB INVESTMENT MANAGEMENT INC 13F CIK 884546 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	65,276	0.26%	+52,365	Jun 30, 2026	carried, not yet filed for the newest quarter
40.1	Schwab Small-Cap Index Fund Fund S000005912 · Registered fund · Jul 31, 2026 SCHWAB CAPITAL TRUST, not summed	55,360	0.22%	—	Jul 31, 2026	SCHWAB CAPITAL TRUST, not summed
40.2	Schwab Total Stock Market Index Fund Fund S000005913 · Registered fund · Jul 31, 2026 SCHWAB CAPITAL TRUST, not summed	12,911	0.05%	0	Jul 31, 2026	SCHWAB CAPITAL TRUST, not summed
41	Bank of New York Mellon Corp 13F CIK 1390777 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	62,473	0.25%	+62,473	Jun 30, 2026	carried, not yet filed for the newest quarter
42	RAYMOND JAMES FINANCIAL INC 13F CIK 720005 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	61,924	0.25%	+61,924	Jun 30, 2026	carried, not yet filed for the newest quarter
43	CITIGROUP INC 13F CIK 831001 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	54,956	0.22%	-20,732	Jun 30, 2026	carried, not yet filed for the newest quarter
44	LPL Financial LLC 13F CIK 1403438 · Broker-dealer · Jun 30, 2026 carried, not yet filed for the newest quarter	54,225	0.22%	+54,225	Jun 30, 2026	carried, not yet filed for the newest quarter
45	Herbets Mitchell H Insider CIK 1644289 · May 26, 2026 Director, issuer-wide	48,984	0.20%	+6,984	May 26, 2026	Director, issuer-wide
46	SG Americas Securities, LLC 13F CIK 1313360 · Non-US institution · Jun 30, 2026 carried, not yet filed for the newest quarter	47,014	0.19%	+18,992	Jun 30, 2026	carried, not yet filed for the newest quarter
47	Engineers Gate Manager LP 13F CIK 1620220 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	41,732	0.17%	+12,732	Jun 30, 2026	carried, not yet filed for the newest quarter
48	Penbrook Management LLC 13F CIK 1381055 · Registered investment adviser · Sep 30, 2026	38,200	0.15%	-675	Sep 30, 2026
49	Polymer Capital Management (HK) LTD 13F CIK 1970465 · Exempt reporting adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	38,000	0.15%	+38,000	Jun 30, 2026	carried, not yet filed for the newest quarter
50	Nuveen, LLC 13F CIK 1871926 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	36,308	0.15%	+36,308	Jun 30, 2026	carried, not yet filed for the newest quarter
50.1	Nuveen Small Cap Blend Index Fund Fund S000005367 · Registered fund · Jul 31, 2026 TIAA-CREF Funds, not summed	29,810	0.12%	—	Jul 31, 2026	TIAA-CREF Funds, not summed

5 more nested rows are not shown here; Every filing lists them all.

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 157 holders

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Key facts CIK 1394056 CUSIP 68247W109 13F (30d) 12 filings 12 filers Visit website Investor relations