Who are Spok Holdings, Inc.'s major customers?

Spok Holdings, Inc. (SPOK) key customers include: Consensus Cloud Solutions, Inc., Consensus Cloud Solutions, Inc., eGain Corporation, eGain Corporation, Health Catalyst, Inc. and 8 more. View the full customer network at chainsifter.com/chain/SPOK.

What sector is Spok Holdings, Inc. in?

Spok Holdings, Inc. (SPOK) operates in the general sector. ChainSifter tracks its verified supply chain relationships including suppliers, customers, and strategic partners.

Spok Holdings, Inc. (SPOK) Supply Chain: 15 Verified Relationships

0Suppliers

13Customers

2Debt Items

13Related Chains

Source-Backed Evidence Depth

Spok Holdings, Inc. (SPOK) is shown with relationship data already present in ChainSifter's database. Counts below come from stored supply-chain records and filing/source URLs where available; missing source URLs are not filled in or estimated.

16Total relationships

2Distinct source URLs

3High confidence

0.748Average confidence

2026-09-13Latest database update

ChainSifter does not infer unreported suppliers, customers, ownership, acquisitions, debt exposure, revenue dependency, or future supply-chain events on this public page.

Spok Holdings, Inc. Suppliers

No suppliers on recordSpok Holdings, Inc. has not yet been matched to upstream suppliers in our database, or is still being processed.

Spok Holdings, Inc. Customers

Ticker	Name	Confidence	Evidence
CCSI	Consensus Cloud Solutions, Inc.	72%	Reciprocal relationship from CCSI graph: Reciprocal relationship from SPOK graph: Reciprocal relationship from CCSI graph: Reciprocal relationship from SPOK graph: vice. As a result, many one-way and…
CCSI	Consensus Cloud Solutions, Inc.	72%	vice. As a result, many one-way and two-way messaging subscribers can readily switch to cellular, personal communications service and other mobile telephone services. The decrease in prices and incre…
EGAN	eGain Corporation	72%	vice. As a result, many one-way and two-way messaging subscribers can readily switch to cellular, personal communications service and other mobile telephone services. The decrease in prices and incre…
EGAN	eGain Corporation	72%	Reciprocal relationship from EGAN graph: Reciprocal relationship from SPOK graph: vice. As a result, many one-way and two-way messaging subscribers can readily switch to cellular, personal communicat…
HCAT	Health Catalyst, Inc.	72%	vice. As a result, many one-way and two-way messaging subscribers can readily switch to cellular, personal communications service and other mobile telephone services. The decrease in prices and incre…
HCAT	Health Catalyst, Inc.	72%	Reciprocal relationship from HCAT graph: Reciprocal relationship from SPOK graph: Reciprocal relationship from HCAT graph: Reciprocal relationship from SPOK graph: vice. As a result, many one-way and…
KORE	KORE Group Holdings, Inc.	72%	Reciprocal relationship from KORE graph: Reciprocal relationship from SPOK graph: Reciprocal relationship from KORE graph: Reciprocal relationship from SPOK graph: Reciprocal relationship from KORE g…
KORE	KORE Group Holdings, Inc.	72%	vice. As a result, many one-way and two-way messaging subscribers can readily switch to cellular, personal communications service and other mobile telephone services. The decrease in prices and incre…
OPRX	OptimizeRx Corporation	72%	Reciprocal relationship from OPRX graph: Reciprocal relationship from SPOK graph: Reciprocal relationship from OPRX graph: Reciprocal relationship from SPOK graph: Reciprocal relationship from OPRX g…
OPRX	OptimizeRx Corporation	72%	vice. As a result, many one-way and two-way messaging subscribers can readily switch to cellular, personal communications service and other mobile telephone services. The decrease in prices and incre…
WEAV	Weave Communications, Inc.	72%	Reciprocal relationship from WEAV graph: Reciprocal relationship from SPOK graph: vice. As a result, many one-way and two-way messaging subscribers can readily switch to cellular, personal communicat…
WEAV	Weave Communications, Inc.	72%	vice. As a result, many one-way and two-way messaging subscribers can readily switch to cellular, personal communications service and other mobile telephone services. The decrease in prices and incre…
SHAREHOLDERS-SPOK-HOLDINGS-INC	SHAREHOLDERS-SPOK-HOLDINGS-INC	62%	included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits…

Spok Holdings, Inc. Debt Obligations

Instrument	Description	Confidence	Evidence
SPOK-DEBT-12708	Warrants outstanding: 0.1	90%	xbrl warrant detail from xbrl 2021-09-02.
SPOK-DEBT	Debt stack $3.2M	90%	Market cache reports total debt of $3.2M.

Spok Holdings, Inc. Acquisitions

No acquisitions on recordNo completed or pending acquisitions found in our database for Spok Holdings, Inc..

Spok Holdings, Inc. Ownership

Holder	Name	Confidence	Evidence
SPOK-OWNER-VANGUARD-CAPITAL-MANAGEMENT-LLC	VANGUARD CAPITAL MANAGEMENT LLC	90%	13F overlay lists VANGUARD CAPITAL MANAGEMENT LLC as top holder; 139 tracked holders.

Spok Holdings, Inc. Extended Supply Chain Network

Ticker	Name	Chain Index	Hops	Relationship Types
NICE	NICE Ltd.	100.00	2
TELNYX	TELNYX	50.00	2
ORCL-PD	ORACLE CORP	50.00	2
WHF	WhiteHorse Finance, Inc.	50.00	2
HSIC	Henry Schein, Inc.	50.00	2
KORE	KORE Group Holdings, Inc.	38.88	1	['customer']
HCAT	Health Catalyst, Inc.	38.88	1	['customer']
WEAV	Weave Communications, Inc.	38.88	1	['customer']
EGAN	eGain Corporation	38.88	1	['customer']
CCSI	Consensus Cloud Solutions, Inc.	38.88	1	['customer']
OPRX	OptimizeRx Corporation	38.88	1	['customer']
ZD	Ziff Davis, Inc.	14.78	2
AON	Aon plc	14.78	2

Spok Holdings, Inc. Supply Chain