GEOS · Geospace Technologies Corp · Shareholders & Ownership

$4.52 +0.13 (+2.85%)

Market Cap

$56.79M

12.94M

Volume · Oct 27 21.94K Avg daily vol (3M) 109.77K

Every disclosed holder of GEOS 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 GEOS

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)	81	5,274,357	40.77%	Yes
Insiders (Forms 3, 4, 5)	10	569,997	4.41%	Yes
13D/G-only blocks	0	0	0.00%	Yes
Remaining	—	7,091,249	54.82%	Rest
Registered funds (N-PORT, not summed)	45	1,250,973	9.67%	No

Shares outstanding: 12,935,603, 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 GEOS

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	Tieton Capital Management, LLC 13F CIK 1381954 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	907,265	7.01%	-4,853	Jun 30, 2026	carried, not yet filed for the newest quarter
2	GRACE & WHITE INC /NY 13F CIK 903064 · Registered investment adviser · Sep 30, 2026	793,498	6.13%	+120,262	Sep 30, 2026
2.1	GRACE & WHITE INC /NY 13G CIK 903064 · Registered investment adviser · Sep 30, 2026 Rule 13d-1(b), qualified institution, not summed	793,498	6.13%	—	Sep 30, 2026	Rule 13d-1(b), qualified institution, not summed
3	VANGUARD CAPITAL MANAGEMENT LLC 13F CIK 2100119 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	515,067	3.98%	-61,965	Jun 30, 2026	carried, not yet filed for the newest quarter
3.1	VANGUARD CAPITAL MANAGEMENT LLC 13G CIK 2100119 · Registered investment adviser · Jun 30, 2026 Rule 13d-1(b), qualified institution, not summed	596,679	4.61%	-61,444	Jun 30, 2026	Rule 13d-1(b), qualified institution, not summed
4	DIMENSIONAL FUND ADVISORS LP 13F CIK 354204 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	392,423	3.03%	-98,593	Jun 30, 2026	carried, not yet filed for the newest quarter
4.1	U.S. MICRO CAP PORTFOLIO Fund S000000948 · Registered fund · Jul 31, 2026 DFA INVESTMENT DIMENSIONS GROUP INC, not summed	106,860	0.83%	0	Jul 31, 2026	DFA INVESTMENT DIMENSIONS GROUP INC, not summed
4.2	U.S. SMALL CAP PORTFOLIO Fund S000000971 · Registered fund · Jul 31, 2026 DFA INVESTMENT DIMENSIONS GROUP INC, not summed	58,642	0.45%	0	Jul 31, 2026	DFA INVESTMENT DIMENSIONS GROUP INC, not summed
4.3	U.S. CORE EQUITY 2 PORTFOLIO Fund S000000980 · Registered fund · Jul 31, 2026 DFA INVESTMENT DIMENSIONS GROUP INC, not summed	34,035	0.26%	-1,482	Jul 31, 2026	DFA INVESTMENT DIMENSIONS GROUP INC, not summed
4.4	Dimensional U.S. Core Equity 2 ETF Fund S000070903 · Registered fund · Jul 31, 2026 Dimensional ETF Trust, not summed	26,311	0.20%	-7,973	Jul 31, 2026	Dimensional ETF Trust, not summed
4.5	Dimensional U.S. Small Cap ETF Fund S000070906 · Registered fund · Jul 31, 2026 Dimensional ETF Trust, not summed	18,921	0.15%	-25,129	Jul 31, 2026	Dimensional ETF Trust, not summed
5	VANGUARD TOTAL STOCK MARKET INDEX FUND Fund S000002848 · Registered fund · Jun 30, 2026 VANGUARD INDEX FUNDS, not summed	357,262	2.76%	-62,500	Jun 30, 2026	VANGUARD INDEX FUNDS, not summed
6	MARSHALL WACE, LLP 13F CIK 1318757 · Exempt reporting adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	301,916	2.33%	+113,110	Jun 30, 2026	carried, not yet filed for the newest quarter
7	BlackRock, Inc. 13F CIK 2012383 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	231,765	1.79%	+6,197	Jun 30, 2026	carried, not yet filed for the newest quarter
7.1	iShares Micro-Cap ETF Fund S000004439 · Registered fund · Jun 30, 2026 iShares Trust, not summed	42,952	0.33%	+11,742	Jun 30, 2026	iShares Trust, not summed
8	US BANCORP \DE\ 13F CIK 36104 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	212,766	1.64%	+85,632	Jun 30, 2026	carried, not yet filed for the newest quarter
9	SEI INVESTMENTS CO 13F CIK 350894 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	199,365	1.54%	-211,541	Jun 30, 2026	carried, not yet filed for the newest quarter
10	Wheeler Walter R. Insider CIK 1550990 · Feb 9, 2025 Director, issuer-wide	172,006	1.33%	+3,500	Feb 9, 2025	Director, issuer-wide
11	GEODE CAPITAL MANAGEMENT, LLC 13F CIK 1214717 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	164,180	1.27%	+12,026	Jun 30, 2026	carried, not yet filed for the newest quarter
12	STATE STREET CORP 13F CIK 93751 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	163,075	1.26%	+26,222	Jun 30, 2026	carried, not yet filed for the newest quarter
12.1	State Street(R) SPDR(R) S&P Kensho Future Security ETF Fund S000059702 · Registered fund · Jun 30, 2026 SPDR SERIES TRUST, not summed	101,686	0.79%	+26,822	Jun 30, 2026	SPDR SERIES TRUST, not summed
13	De Lisle Partners LLP 13F CIK 2011184 · Non-US institution · Jun 30, 2026 carried, not yet filed for the newest quarter	147,133	1.14%	0	Jun 30, 2026	carried, not yet filed for the newest quarter
14	VANGUARD EXTENDED MARKET INDEX FUND Fund S000002841 · Registered fund · Jun 30, 2026 VANGUARD INDEX FUNDS, not summed	145,758	1.13%	-521	Jun 30, 2026	VANGUARD INDEX FUNDS, not summed
15	ROBOTTI ROBERT 13F CIK 1105838 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	128,436	0.99%	+128,436	Jun 30, 2026	carried, not yet filed for the newest quarter
16	TWO SIGMA INVESTMENTS, LP 13F CIK 1179392 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	82,184	0.64%	+8,277	Jun 30, 2026	carried, not yet filed for the newest quarter
17	BRIDGEWAY CAPITAL MANAGEMENT, LLC 13F CIK 1107261 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	79,693	0.62%	+900	Jun 30, 2026	carried, not yet filed for the newest quarter
17.1	Ultra-Small Company Market Fund Fund S000004424 · Registered fund · Jun 30, 2026 Bridgeway Funds, Inc., not summed	30,000	0.23%	0	Jun 30, 2026	Bridgeway Funds, Inc., not summed
17.2	Omni Small-Cap Value Fund Fund S000033567 · Registered fund · Jun 30, 2026 Bridgeway Funds, Inc., not summed	26,102	0.20%	0	Jun 30, 2026	Bridgeway Funds, Inc., not summed
18	VANGUARD FIDUCIARY TRUST CO 13F CIK 933478 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	76,586	0.59%	+521	Jun 30, 2026	carried, not yet filed for the newest quarter
19	Adams Robbin B. Insider CIK 1550921 · Nov 21, 2024 SVP & Chief Technical Officer, issuer-wide	74,921	0.58%	+1,500	Nov 21, 2024	SVP & Chief Technical Officer, issuer-wide
20	Glenorchy Capital Ltd 13F CIK 2008506 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	68,488	0.53%	-104,851	Jun 30, 2026	carried, not yet filed for the newest quarter
21	DAVIS THOMAS L Insider CIK 1049658 · Feb 9, 2026 Director, issuer-wide	65,454	0.51%	+3,500	Feb 9, 2026	Director, issuer-wide
22	Curda Robert L. Insider CIK 1797979 · Dec 5, 2025 Vice President & CFO, issuer-wide	61,112	0.47%	-165	Dec 5, 2025	Vice President & CFO, issuer-wide
23	CITADEL ADVISORS LLC 13F CIK 1423053 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	58,018	0.45%	+25,300	Jun 30, 2026	carried, not yet filed for the newest quarter
24	Miles Richard F Insider CIK 1378704 · Feb 9, 2026 Director, issuer-wide	50,100	0.39%	+3,500	Feb 9, 2026	Director, issuer-wide
25	EagleClaw Capital Managment, LLC 13F CIK 1607636 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	50,015	0.39%	-32,000	Jun 30, 2026	carried, not yet filed for the newest quarter
26	ACUITAS US MICROCAP FUND Fund S000045890 · Registered fund · Jun 30, 2026 FORUM FUNDS II, not summed	47,250	0.37%	-1,260	Jun 30, 2026	FORUM FUNDS II, not summed
27	RENAISSANCE TECHNOLOGIES LLC 13F CIK 1037389 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	44,299	0.34%	+44,299	Jun 30, 2026	carried, not yet filed for the newest quarter
28	Giesinger Edgar R. JR. Insider CIK 1658831 · Feb 9, 2026 Director, issuer-wide	43,000	0.33%	+3,500	Feb 9, 2026	Director, issuer-wide
29	ACADIAN ASSET MANAGEMENT LLC 13F CIK 916542 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	42,713	0.33%	+42,713	Jun 30, 2026	carried, not yet filed for the newest quarter
30	Kelley Richard James Insider CIK 2022461 · Dec 5, 2025 President & CEO, issuer-wide	41,977	0.32%	-275	Dec 5, 2025	President & CEO, issuer-wide
31	IRONWOOD INVESTMENT MANAGEMENT LLC 13F CIK 1127761 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	36,279	0.28%	+237	Jun 30, 2026	carried, not yet filed for the newest quarter
32	JACOBS LEVY EQUITY MANAGEMENT, INC 13F CIK 884414 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	35,573	0.28%	+35,573	Jun 30, 2026	carried, not yet filed for the newest quarter
33	Ashworth Margaret Insider CIK 1833160 · Feb 9, 2025 Director, issuer-wide	34,400	0.27%	+3,500	Feb 9, 2025	Director, issuer-wide
34	SUSQUEHANNA INTERNATIONAL GROUP, LLP 13F CIK 1446194 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	33,029	0.26%	-113,366	Jun 30, 2026	carried, not yet filed for the newest quarter
35	Kingsview Wealth Management, LLC 13F CIK 1791965 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	31,283	0.24%	+2,961	Jun 30, 2026	carried, not yet filed for the newest quarter
36	HRT FINANCIAL LP 13F CIK 1475597 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	30,656	0.24%	+30,656	Jun 30, 2026	carried, not yet filed for the newest quarter
37	Cambridge Investment Research Advisors, Inc. 13F CIK 1419186 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	29,865	0.23%	-14,432	Jun 30, 2026	carried, not yet filed for the newest quarter
38	NORTHERN TRUST CORP 13F CIK 73124 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	28,717	0.22%	-11,879	Jun 30, 2026	carried, not yet filed for the newest quarter
39	AMERICAN CENTURY COMPANIES INC 13F CIK 748054 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	28,201	0.22%	-1,118	Jun 30, 2026	carried, not yet filed for the newest quarter
40	GOLDMAN SACHS GROUP INC 13F CIK 886982 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	25,800	0.20%	+25,800	Jun 30, 2026	carried, not yet filed for the newest quarter
40.1	Goldman Sachs Absolute Return Tracker Fund Fund S000020314 · Registered fund · Aug 31, 2026 GOLDMAN SACHS TRUST, not summed	13,294	0.10%	+1,936	Aug 31, 2026	GOLDMAN SACHS TRUST, not summed
41	Avantis U.S. Small Cap Equity ETF Fund S000074835 · Registered fund · May 31, 2026 American Century ETF Trust, not summed	24,799	0.19%	0	May 31, 2026	American Century ETF Trust, not summed
42	Mraz, Amerine & Associates, Inc. 13F CIK 1542324 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	24,385	0.19%	+304	Jun 30, 2026	carried, not yet filed for the newest quarter
43	ELEVATION POINT WEALTH PARTNERS, LLC 13F CIK 1744349 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	24,313	0.19%	-42	Jun 30, 2026	carried, not yet filed for the newest quarter
44	Vestmark Advisory Solutions, Inc. 13F CIK 1736982 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	24,313	0.19%	0	Jun 30, 2026	carried, not yet filed for the newest quarter
45	IMC-Chicago, LLC 13F CIK 1452861 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	23,132	0.18%	+9,634	Jun 30, 2026	carried, not yet filed for the newest quarter
46	COMMONWEALTH EQUITY SERVICES, LLC 13F CIK 312272 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	22,496	0.17%	+611	Jun 30, 2026	carried, not yet filed for the newest quarter
47	JANE STREET GROUP, LLC 13F CIK 1595888 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	21,271	0.16%	+21,271	Jun 30, 2026	carried, not yet filed for the newest quarter
48	Empowered Funds, LLC 13F CIK 1592828 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	20,291	0.16%	0	Jun 30, 2026	carried, not yet filed for the newest quarter
48.1	EA Bridgeway Omni Small-Cap Value ETF Fund S000078089 · Registered fund · Jun 30, 2026 EA Series Trust, not summed	20,291	0.16%	0	Jun 30, 2026	EA Series Trust, not summed
49	Tannin Capital LLC 13F CIK 2110834 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	19,657	0.15%	+2,448	Jun 30, 2026	carried, not yet filed for the newest quarter
50	AXQ CAPITAL, LP 13F CIK 1916908 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	19,637	0.15%	+19,637	Jun 30, 2026	carried, not yet filed for the newest quarter

7 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 108 holders

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

Key facts CIK 1001115 CUSIP 37364X109 13F (30d) 7 filings 7 filers Visit website Investor relations