SPOK US Equity

Spok Holdings, Inc

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Communication Services · Radiotelephone Communications · CIK 1289945 · FYE 1231

$10.89

+0.08 (+0.74%)

USD · as of 2026-07-28 · marketstack

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Institutional ownership· 13F filers holding SPOK · 2026-Q1 methodology → sources →

138 holders

% of shares outstanding held

50.2%

Shares held (13F)

10,489,614

Reporting holders

138

Top holders

largest 100 of 138 · Δ vs 2025-Q4

#	Holder	Shares	Value	% of shares out	Δ QoQ
1	BlackRock, Inc.	1,676,2271.7M	$18M	8.03%	TRIM -7%
2	RENAISSANCE TECHNOLOGIES LLC	1,261,5791.3M	$14M	6.04%	—
3	VANGUARD CAPITAL MANAGEMENT LLC	859,530859,530	$9M	4.12%	NEW†
4	DIMENSIONAL FUND ADVISORS LP	715,869715,869	$8M	3.43%	—
5	GEODE CAPITAL MANAGEMENT, LLC	545,718545,718	$6M	2.61%	TRIM -9%
6	STATE STREET CORP	461,790461,790	$5M	2.21%	ADD 3%
7	HighTower Advisors, LLC	381,815381,815	$4M	1.83%	—
8	VANGUARD PORTFOLIO MANAGEMENT LLC	265,028265,028	$3M	1.27%	NEW
9	GOLDMAN SACHS GROUP INC	219,581219,581	$2M	1.05%	TRIM -39%
10	Bank of New York Mellon Corp	217,803217,803	$2M	1.04%	ADD 2%
11	NORTHERN TRUST CORP	216,543216,543	$2M	1.04%	—
12	CSM Advisors, LLC	213,130213,130	$2M	1.02%	TRIM -19%
13	Uniplan Investment Counsel, Inc.	209,602209,602	$2M	1.00%	ADD 30%
14	Qube Research & Technologies Ltd	172,057172,057	$2M	0.82%	TRIM -3%
15	MORGAN STANLEY	159,826159,826	$2M	0.77%	TRIM -10%
16	Connor, Clark & Lunn Investment Management Ltd.	144,851144,851	$2M	0.69%	TRIM -26%
17	VANGUARD FIDUCIARY TRUST CO	129,248129,248	$1M	0.62%	NEW
18	Trexquant Investment LP	128,856128,856	$1M	0.62%	TRIM -24%
19	North Star Investment Management Corp.	122,000122,000	$1M	0.58%	—
20	JACOBS LEVY EQUITY MANAGEMENT, INC	116,810116,810	$1M	0.56%	—
21	MARSHALL WACE, LLP	112,789112,789	$1M	0.54%	NEW
22	UNITED CAPITAL FINANCIAL ADVISORS, LLC	104,723104,723	$1M	0.50%	NEW
23	Point72 Asset Management, L.P.	89,62789,627	$976,934	0.43%	ADD 379%
24	D. E. Shaw & Co., Inc.	89,45189,451	$975,015	0.43%	ADD 27%
25	JANE STREET GROUP, LLC	86,52486,524	$943,112	0.41%	ADD 529%
26	GSA CAPITAL PARTNERS LLP	85,82485,824	$935,000	0.41%	ADD 114%
27	PANAGORA ASSET MANAGEMENT INC	78,29578,295	$853,415	0.37%	TRIM -16%
28	FIDELIS CAPITAL PARTNERS, LLC	75,00175,001	$817,511	0.36%	NEW
29	Nuveen, LLC	73,33673,336	$799,363	0.35%	—
30	JPMORGAN CHASE & CO	69,69369,693	$783,349	0.33%	TRIM -24%
31	Numerai GP LLC	69,01669,016	$752,274	0.33%	NEW
32	FIRST TRUST ADVISORS LP	65,49865,498	$713,928	0.31%	—
33	Engineers Gate Manager LP	64,06864,068	$698,341	0.31%	ADD 76%
34	CHARLES SCHWAB INVESTMENT MANAGEMENT INC	56,03556,035	$610,782	0.27%	TRIM -8%
35	Campbell & CO Investment Adviser LLC	50,86950,869	$554,472	0.24%	ADD 4%
36	Keebeck Wealth Management	50,00050,000	$545,000	0.24%	ADD 25%
37	Man Group plc	48,32548,325	$526,743	0.23%	ADD 83%
38	AMERICAN CENTURY COMPANIES INC	43,36843,368	$472,711	0.21%	—
39	AQR CAPITAL MANAGEMENT LLC	43,13243,132	$470,139	0.21%	ADD 164%
40	VICTORY CAPITAL MANAGEMENT INC	42,81642,816	$466,694	0.20%	ADD 16%
41	HSBC HOLDINGS PLC	41,49941,499	$458,356	0.20%	TRIM -66%
42	Dynamic Technology Lab Private Ltd	37,54437,544	$409,230	0.18%	NEW
43	MILLENNIUM MANAGEMENT LLC	37,15537,155	$404,990	0.18%	TRIM -70%
44	ALLIANCEBERNSTEIN L.P.	28,16028,160	$371,430	0.13%	ADD 17%
45	RHUMBLINE ADVISERS	31,19431,194	$340,006	0.15%	—
46	Invesco Ltd.	30,47530,475	$332,178	0.15%	—
47	UBS Group AG	29,01829,018	$316,296	0.14%	TRIM -49%
48	BRIDGEWAY CAPITAL MANAGEMENT, LLC	26,60026,600	$289,940	0.13%	NEW
49	BANK OF AMERICA CORP /DE/	26,52826,528	$289,155	0.13%	TRIM -27%
50	Quantinno Capital Management LP	26,15026,150	$285,040	0.13%	TRIM -72%
51	MARTINGALE ASSET MANAGEMENT L P	23,02523,025	$250,973	0.11%	TRIM -3%
52	STATE OF WISCONSIN INVESTMENT BOARD	20,30020,300	$221,270	0.10%	ADD 83%
53	TWO SIGMA INVESTMENTS, LP	19,90019,900	$216,910	0.10%	TRIM -68%
54	Cambria Investment Management, L.P.	19,74419,744	$215,210	0.09%	ADD 62%
55	WELLS FARGO & COMPANY/MN	18,99118,991	$207,000	0.09%	TRIM -36%
56	Hennion & Walsh Asset Management, Inc.	18,70718,707	$203,906	0.09%	—
57	OCCUDO QUANTITATIVE STRATEGIES LP	18,94818,948	$202,554	0.09%	ADD 40%
58	DEUTSCHE BANK AG\	17,97417,974	$195,917	0.09%	ADD 37%
59	CITADEL ADVISORS LLC	17,77517,775	$193,748	0.09%	TRIM -64%
60	Aquatic Capital Management LLC	17,34217,342	$189,028	0.08%	ADD 249%
61	AMERIPRISE FINANCIAL INC	16,88116,881	$184,003	0.08%	TRIM -16%
62	Significant Wealth Partners LLC	16,68316,683	$181,845	0.08%	ADD 13%
63	BARCLAYS PLC	15,32015,320	$166,989	0.07%	TRIM -66%
64	Empowered Funds, LLC	15,20315,203	$165,713	0.07%	NEW
65	CANADA PENSION PLAN INVESTMENT BOARD	15,20015,200	$165,680	0.07%	—
66	FMR LLC	15,02915,029	$163,819	0.07%	TRIM -88%
67	PRICE T ROWE ASSOCIATES INC /MD/	14,79114,791	$162,000	0.07%	ADD 38%
68	EntryPoint Capital, LLC	14,85014,850	$161,865	0.07%	NEW
69	Magnetar Financial LLC	13,90413,904	$151,553	0.07%	TRIM -35%
70	SUSQUEHANNA INTERNATIONAL GROUP, LLP	13,06413,064	$142,398	0.06%	NEW
71	Squarepoint Ops LLC	12,48112,481	$136,043	0.06%	TRIM -23%
72	Brady Martz Wealth Solutions, LLC	12,22012,220	$133,198	0.06%	NEW
73	Focus Partners Advisor Solutions, LLC	12,11112,111	$132,010	0.06%	NEW
74	Quadrature Capital Ltd	11,36711,367	$123,900	0.05%	NEW
75	PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO	10,67310,673	$116,336	0.05%	—
76	Grantham, Mayo, Van Otterloo & Co. LLC	10,47310,473	$114,156	0.05%	TRIM -15%
77	AXQ CAPITAL, LP	10,28310,283	$112,085	0.05%	NEW
78	Redhawk Wealth Advisors, Inc.	10,13410,134	$110,456	0.05%	NEW
79	OXFORD ASSET MANAGEMENT LLP	10,02010,020	$109,218	0.05%	TRIM -3%
80	State of Wyoming	10,01310,013	$109,142	0.05%	ADD 160%
81	MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd.	9,6839,683	$105,545	0.05%	ADD 3%
82	Vanguard Global Advisers, LLC	8,9878,987	$97,958	0.04%	NEW
83	Russell Investments Group, Ltd.	7,8517,851	$85,575	0.04%	ADD 110%
84	VIRTUS ADVISERS, LLC	7,1257,125	$77,663	0.03%	TRIM -51%
85	Truvestments Capital LLC	7,0147,014	$76,451	0.03%	TRIM -21%
86	Police & Firemen's Retirement System of New Jersey	6,5976,597	$71,907	0.03%	—
87	MetLife Investment Management, LLC	6,4726,472	$70,545	0.03%	TRIM -41%
88	CWM, LLC	5,8745,874	$64,027	0.03%	ADD 585%
89	New Age Alpha Advisors, LLC	5,8555,855	$63,820	0.03%	—
90	Triumph Capital Management	5,5015,501	$59,961	0.03%	ADD 15%
91	BNP PARIBAS FINANCIAL MARKETS	4,3894,389	$47,840	0.02%	TRIM -6%
92	Tower Research Capital LLC (TRC)	4,1684,168	$45,431	0.02%	ADD 54%
93	Legal & General Group Plc	3,9543,954	$43,099	0.02%	—
94	Rockefeller Capital Management L.P.	2,7442,744	$29,910	0.01%	ADD 399%
95	CANADA LIFE ASSURANCE Co	2,5652,565	$28,000	0.01%	ADD 4%
96	Ameritas Investment Partners, Inc.	2,0802,080	$22,672	0.01%	—
97	Larson Financial Group LLC	2,0002,000	$21,800	0.01%	—
98	SBI Securities Co., Ltd.	1,8591,859	$20,567	0.01%	ADD 6%
99	CITIGROUP INC	1,6271,627	$17,735	0.01%	TRIM -77%
100	CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM	1,1021,102	$12,012	0.01%	TRIM -12%

† a filer this large appearing as NEW usually reflects a renamed or succeeded filing entity (the old name stops filing the same quarter) — not a brand-new position.

Rows rank by the value each filer reported — 13F filers price their own positions, so a holder with fewer shares can rank just above one with more.

Holder trends· top 15 holders · shares held over 6 quarters

green added · red trimmed

Holder

2024-Q4

2025-Q1

2025-Q2

2025-Q3

2025-Q4

2026-Q1

Latest value

BlackRock, Inc.

1.4M

1.5M

1.7M

1.9M

1.8M

1.7M

$18M

RENAISSANCE TECHNOLOGIES LLC

976K

1.0M

1.1M

1.2M

1.3M

$14M

VANGUARD CAPITAL MANAGEMENT LLC

—

860K

$9M

DIMENSIONAL FUND ADVISORS LP

708K

700K

711K

719K

704K

716K

$8M

GEODE CAPITAL MANAGEMENT, LLC

514K

488K

518K

601K

599K

546K

$6M

STATE STREET CORP

439K

437K

445K

457K

447K

462K

$5M

HighTower Advisors, LLC

667K

523K

453K

408K

382K

$4M

VANGUARD PORTFOLIO MANAGEMENT LLC

—

265K

$3M

GOLDMAN SACHS GROUP INC

391K

522K

530K

396K

362K

220K

$2M

Bank of New York Mellon Corp

200K

190K

196K

213K

218K

$2M

NORTHERN TRUST CORP

207K

217K

243K

241K

217K

$2M

CSM Advisors, LLC

—

349K

334K

263K

213K

$2M

Uniplan Investment Counsel, Inc.

204K

205K

188K

161K

210K

$2M

Qube Research & Technologies Ltd

72K

125K

146K

162K

178K

172K

$2M

MORGAN STANLEY

158K

169K

152K

144K

178K

160K

$2M

Shares reported each quarter by the largest current holders. Green = added vs the prior filing, red = trimmed, grey = roughly held; a dash is a quarter with no 13F on file (a gap is skipped, not read as an exit). 13F is filed up to 45 days after quarter-end. Up to 40 quarters (10 years) available — use the selector above.

Institutional footprint by quarter

Line breaks are honest gaps — quarters with no 13F record, or a suppressed % — never interpolated. % of shares outstanding uses today's share count for every quarter (the only count stored).

Quarter	Holders	Shares held	% shares out	Value held
2026-Q1	138	10,489,614	50.2%	$114M
2025-Q4	133	11,111,322	53.2%	$147M
2025-Q3	143	11,573,849

Short interest has its own tab now — open SI →

Source: SEC Form 13F — every institution manager (≥ $100M in 13F securities) reporting a long US-listed position, across ~10,250 filers over 10 years of history. 13F is long-only, US-listed, filed up to 45 days after quarter-end.

Activists & large holders· Schedule 13D/G beneficial owners · SPOK

Large holders — 13G, passive (top 2 by % of class)

Holder	% of class	Type	As of
RENAISSANCE TECHNOLOGIES LLC	5.13%	QII	2025-04-07	SEC →
VANGUARD GROUP INC	0%	QII	2026-03-13	SEC →

Source: SEC Schedule 13D/13G structured XML. 13D = active intent; 13G filers report passively (Rule 13d-1(b) QII / 13d-1(c) Passive / 13d-1(d) Exempt) and are not activists. Percent and delta are the group aggregate the filing reports. Structured 13D/G coverage begins December 2024 (SEC XML mandate).

Institutional ownership· 13F filers holding SPOK · 2026-Q1 methodology → sources →

138 holders

% of shares outstanding held

50.2%

Shares held (13F)

10,489,614

Reporting holders

138

Top holders

largest 100 of 138 · Δ vs 2025-Q4

#	Holder	Shares	Value	% of shares out	Δ QoQ
1	BlackRock, Inc.	1,676,2271.7M	$18M	8.03%	TRIM -7%
2	RENAISSANCE TECHNOLOGIES LLC	1,261,5791.3M	$14M	6.04%	—
3	VANGUARD CAPITAL MANAGEMENT LLC	859,530859,530	$9M	4.12%	NEW†
4	DIMENSIONAL FUND ADVISORS LP	715,869715,869	$8M	3.43%	—
5	GEODE CAPITAL MANAGEMENT, LLC	545,718545,718	$6M	2.61%	TRIM -9%
6	STATE STREET CORP	461,790461,790	$5M	2.21%	ADD 3%
7	HighTower Advisors, LLC	381,815381,815	$4M	1.83%	—
8	VANGUARD PORTFOLIO MANAGEMENT LLC	265,028265,028	$3M	1.27%	NEW
9	GOLDMAN SACHS GROUP INC	219,581219,581	$2M	1.05%	TRIM -39%
10	Bank of New York Mellon Corp	217,803217,803	$2M	1.04%	ADD 2%
11	NORTHERN TRUST CORP	216,543216,543	$2M	1.04%	—
12	CSM Advisors, LLC	213,130213,130	$2M	1.02%	TRIM -19%
13	Uniplan Investment Counsel, Inc.	209,602209,602	$2M	1.00%	ADD 30%
14	Qube Research & Technologies Ltd	172,057172,057	$2M	0.82%	TRIM -3%
15	MORGAN STANLEY	159,826159,826	$2M	0.77%	TRIM -10%
16	Connor, Clark & Lunn Investment Management Ltd.	144,851144,851	$2M	0.69%	TRIM -26%
17	VANGUARD FIDUCIARY TRUST CO	129,248129,248	$1M	0.62%	NEW
18	Trexquant Investment LP	128,856128,856	$1M	0.62%	TRIM -24%
19	North Star Investment Management Corp.	122,000122,000	$1M	0.58%	—
20	JACOBS LEVY EQUITY MANAGEMENT, INC	116,810116,810	$1M	0.56%	—
21	MARSHALL WACE, LLP	112,789112,789	$1M	0.54%	NEW
22	UNITED CAPITAL FINANCIAL ADVISORS, LLC	104,723104,723	$1M	0.50%	NEW
23	Point72 Asset Management, L.P.	89,62789,627	$976,934	0.43%	ADD 379%
24	D. E. Shaw & Co., Inc.	89,45189,451	$975,015	0.43%	ADD 27%
25	JANE STREET GROUP, LLC	86,52486,524	$943,112	0.41%	ADD 529%
26	GSA CAPITAL PARTNERS LLP	85,82485,824	$935,000	0.41%	ADD 114%
27	PANAGORA ASSET MANAGEMENT INC	78,29578,295	$853,415	0.37%	TRIM -16%
28	FIDELIS CAPITAL PARTNERS, LLC	75,00175,001	$817,511	0.36%	NEW
29	Nuveen, LLC	73,33673,336	$799,363	0.35%	—
30	JPMORGAN CHASE & CO	69,69369,693	$783,349	0.33%	TRIM -24%
31	Numerai GP LLC	69,01669,016	$752,274	0.33%	NEW
32	FIRST TRUST ADVISORS LP	65,49865,498	$713,928	0.31%	—
33	Engineers Gate Manager LP	64,06864,068	$698,341	0.31%	ADD 76%
34	CHARLES SCHWAB INVESTMENT MANAGEMENT INC	56,03556,035	$610,782	0.27%	TRIM -8%
35	Campbell & CO Investment Adviser LLC	50,86950,869	$554,472	0.24%	ADD 4%
36	Keebeck Wealth Management	50,00050,000	$545,000	0.24%	ADD 25%
37	Man Group plc	48,32548,325	$526,743	0.23%	ADD 83%
38	AMERICAN CENTURY COMPANIES INC	43,36843,368	$472,711	0.21%	—
39	AQR CAPITAL MANAGEMENT LLC	43,13243,132	$470,139	0.21%	ADD 164%
40	VICTORY CAPITAL MANAGEMENT INC	42,81642,816	$466,694	0.20%	ADD 16%
41	HSBC HOLDINGS PLC	41,49941,499	$458,356	0.20%	TRIM -66%
42	Dynamic Technology Lab Private Ltd	37,54437,544	$409,230	0.18%	NEW
43	MILLENNIUM MANAGEMENT LLC	37,15537,155	$404,990	0.18%	TRIM -70%
44	ALLIANCEBERNSTEIN L.P.	28,16028,160	$371,430	0.13%	ADD 17%
45	RHUMBLINE ADVISERS	31,19431,194	$340,006	0.15%	—
46	Invesco Ltd.	30,47530,475	$332,178	0.15%	—
47	UBS Group AG	29,01829,018	$316,296	0.14%	TRIM -49%
48	BRIDGEWAY CAPITAL MANAGEMENT, LLC	26,60026,600	$289,940	0.13%	NEW
49	BANK OF AMERICA CORP /DE/	26,52826,528	$289,155	0.13%	TRIM -27%
50	Quantinno Capital Management LP	26,15026,150	$285,040	0.13%	TRIM -72%
51	MARTINGALE ASSET MANAGEMENT L P	23,02523,025	$250,973	0.11%	TRIM -3%
52	STATE OF WISCONSIN INVESTMENT BOARD	20,30020,300	$221,270	0.10%	ADD 83%
53	TWO SIGMA INVESTMENTS, LP	19,90019,900	$216,910	0.10%	TRIM -68%
54	Cambria Investment Management, L.P.	19,74419,744	$215,210	0.09%	ADD 62%
55	WELLS FARGO & COMPANY/MN	18,99118,991	$207,000	0.09%	TRIM -36%
56	Hennion & Walsh Asset Management, Inc.	18,70718,707	$203,906	0.09%	—
57	OCCUDO QUANTITATIVE STRATEGIES LP	18,94818,948	$202,554	0.09%	ADD 40%
58	DEUTSCHE BANK AG\	17,97417,974	$195,917	0.09%	ADD 37%
59	CITADEL ADVISORS LLC	17,77517,775	$193,748	0.09%	TRIM -64%
60	Aquatic Capital Management LLC	17,34217,342	$189,028	0.08%	ADD 249%
61	AMERIPRISE FINANCIAL INC	16,88116,881	$184,003	0.08%	TRIM -16%
62	Significant Wealth Partners LLC	16,68316,683	$181,845	0.08%	ADD 13%
63	BARCLAYS PLC	15,32015,320	$166,989	0.07%	TRIM -66%
64	Empowered Funds, LLC	15,20315,203	$165,713	0.07%	NEW
65	CANADA PENSION PLAN INVESTMENT BOARD	15,20015,200	$165,680	0.07%	—
66	FMR LLC	15,02915,029	$163,819	0.07%	TRIM -88%
67	PRICE T ROWE ASSOCIATES INC /MD/	14,79114,791	$162,000	0.07%	ADD 38%
68	EntryPoint Capital, LLC	14,85014,850	$161,865	0.07%	NEW
69	Magnetar Financial LLC	13,90413,904	$151,553	0.07%	TRIM -35%
70	SUSQUEHANNA INTERNATIONAL GROUP, LLP	13,06413,064	$142,398	0.06%	NEW
71	Squarepoint Ops LLC	12,48112,481	$136,043	0.06%	TRIM -23%
72	Brady Martz Wealth Solutions, LLC	12,22012,220	$133,198	0.06%	NEW
73	Focus Partners Advisor Solutions, LLC	12,11112,111	$132,010	0.06%	NEW
74	Quadrature Capital Ltd	11,36711,367	$123,900	0.05%	NEW
75	PUBLIC EMPLOYEES RETIREMENT SYSTEM OF OHIO	10,67310,673	$116,336	0.05%	—
76	Grantham, Mayo, Van Otterloo & Co. LLC	10,47310,473	$114,156	0.05%	TRIM -15%
77	AXQ CAPITAL, LP	10,28310,283	$112,085	0.05%	NEW
78	Redhawk Wealth Advisors, Inc.	10,13410,134	$110,456	0.05%	NEW
79	OXFORD ASSET MANAGEMENT LLP	10,02010,020	$109,218	0.05%	TRIM -3%
80	State of Wyoming	10,01310,013	$109,142	0.05%	ADD 160%
81	MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd.	9,6839,683	$105,545	0.05%	ADD 3%
82	Vanguard Global Advisers, LLC	8,9878,987	$97,958	0.04%	NEW
83	Russell Investments Group, Ltd.	7,8517,851	$85,575	0.04%	ADD 110%
84	VIRTUS ADVISERS, LLC	7,1257,125	$77,663	0.03%	TRIM -51%
85	Truvestments Capital LLC	7,0147,014	$76,451	0.03%	TRIM -21%
86	Police & Firemen's Retirement System of New Jersey	6,5976,597	$71,907	0.03%	—
87	MetLife Investment Management, LLC	6,4726,472	$70,545	0.03%	TRIM -41%
88	CWM, LLC	5,8745,874	$64,027	0.03%	ADD 585%
89	New Age Alpha Advisors, LLC	5,8555,855	$63,820	0.03%	—
90	Triumph Capital Management	5,5015,501	$59,961	0.03%	ADD 15%
91	BNP PARIBAS FINANCIAL MARKETS	4,3894,389	$47,840	0.02%	TRIM -6%
92	Tower Research Capital LLC (TRC)	4,1684,168	$45,431	0.02%	ADD 54%
93	Legal & General Group Plc	3,9543,954	$43,099	0.02%	—
94	Rockefeller Capital Management L.P.	2,7442,744	$29,910	0.01%	ADD 399%
95	CANADA LIFE ASSURANCE Co	2,5652,565	$28,000	0.01%	ADD 4%
96	Ameritas Investment Partners, Inc.	2,0802,080	$22,672	0.01%	—
97	Larson Financial Group LLC	2,0002,000	$21,800	0.01%	—
98	SBI Securities Co., Ltd.	1,8591,859	$20,567	0.01%	ADD 6%
99	CITIGROUP INC	1,6271,627	$17,735	0.01%	TRIM -77%
100	CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM	1,1021,102	$12,012	0.01%	TRIM -12%

† a filer this large appearing as NEW usually reflects a renamed or succeeded filing entity (the old name stops filing the same quarter) — not a brand-new position.

Rows rank by the value each filer reported — 13F filers price their own positions, so a holder with fewer shares can rank just above one with more.

Holder trends· top 15 holders · shares held over 6 quarters

green added · red trimmed

Holder

2024-Q4

2025-Q1

2025-Q2

2025-Q3

2025-Q4

2026-Q1

Latest value

BlackRock, Inc.

1.4M

1.5M

1.7M

1.9M

1.8M

1.7M

$18M

RENAISSANCE TECHNOLOGIES LLC

976K

1.0M

1.1M

1.2M

1.3M

$14M

VANGUARD CAPITAL MANAGEMENT LLC

—

860K

$9M

DIMENSIONAL FUND ADVISORS LP

708K

700K

711K

719K

704K

716K

$8M

GEODE CAPITAL MANAGEMENT, LLC

514K

488K

518K

601K

599K

546K

$6M

STATE STREET CORP

439K

437K

445K

457K

447K

462K

$5M

HighTower Advisors, LLC

667K

523K

453K

408K

382K

$4M

VANGUARD PORTFOLIO MANAGEMENT LLC

—

265K

$3M

GOLDMAN SACHS GROUP INC

391K

522K

530K

396K

362K

220K

$2M

Bank of New York Mellon Corp

200K

190K

196K

213K

218K

$2M

NORTHERN TRUST CORP

207K

217K

243K

241K

217K

$2M

CSM Advisors, LLC

—

349K

334K

263K

213K

$2M

Uniplan Investment Counsel, Inc.

204K

205K

188K

161K

210K

$2M

Qube Research & Technologies Ltd

72K

125K

146K

162K

178K

172K

$2M

MORGAN STANLEY

158K

169K

152K

144K

178K

160K

$2M

Institutional footprint by quarter

Line breaks are honest gaps — quarters with no 13F record, or a suppressed % — never interpolated. % of shares outstanding uses today's share count for every quarter (the only count stored).

Quarter	Holders	Shares held	% shares out	Value held
2026-Q1	138	10,489,614	50.2%	$114M
2025-Q4	133	11,111,322	53.2%	$147M
2025-Q3	143	11,573,849

Short interest has its own tab now — open SI →

Activists & large holders· Schedule 13D/G beneficial owners · SPOK

Large holders — 13G, passive (top 2 by % of class)

Holder	% of class	Type	As of
RENAISSANCE TECHNOLOGIES LLC	5.13%	QII	2025-04-07	SEC →
VANGUARD GROUP INC	0%	QII	2026-03-13	SEC →

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Institutional ownership· 13F filers holding SPOK · 2026-Q1 methodology → sources →

Top holders

Holder trends· top 15 holders · shares held over 6 quarters

Institutional footprint by quarter

Activists & large holders· Schedule 13D/G beneficial owners · SPOK

Institutional ownership· 13F filers holding SPOK · 2026-Q1 methodology → sources →

Top holders

Holder trends· top 15 holders · shares held over 6 quarters

Institutional footprint by quarter

Activists & large holders· Schedule 13D/G beneficial owners · SPOK

SPOK US Equity