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Companies using Si21

As of 14 October 2026, Firmable tracks 7 companies across 9 countries running Si21. See who they are, and who to call.

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Companies using Si21

Showing 3 of 7 companies

Vitruvian Partners

vitruvianpartners.com · Investment management · 51–250 employees · 1 web property observed

Last seen 10 Oct 2026 The most recent date Firmable detected Si21 at this company.

Decision makers · 11 on file Senior people on file at this company. Firmable holds their names, emails and mobiles.

Managing Director MobileEmail
Vice President MobileEmail

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Signals Recent events at this company, such as a leadership change, funding or a new office.

Vitruvian Partners invested into Angle Health $200M in Series C on Sep 18th '26. · 18 Sep 2026

Battery Ventures sells assets to Vitruvian Partners. · 16 Sep 2026

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Housing Croatia

housing.hr · E-learning and online education · 51–250 employees · 1 web property observed

Last seen 11 Oct 2026 The most recent date Firmable detected Si21 at this company.

Decision makers · 3 on file Senior people on file at this company. Firmable holds their names, emails and mobiles.

Assistant Director of IT MobileEmail
Manager MobileEmail

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Signals Recent events at this company, such as a leadership change, funding or a new office.

No signals recorded

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SoftNET

softnet.eu · Telecommunications services · 11–50 employees · 7 web properties observed

Last seen 13 Oct 2026 The most recent date Firmable detected Si21 at this company.

Decision makers · 4 on file Senior people on file at this company. Firmable holds their names, emails and mobiles.

Network Manager and Infrastructure Lead MobileEmail
Sales Manager Email

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Signals Recent events at this company, such as a leadership change, funding or a new office.

No signals recorded

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Who uses Si21

A breakdown of the 7 companies running Si21.

Top industries

Education and training2
Financial services1
Information technology and services1
Media and telecommunications1
Professional and business services1
Retail trade1

Company size

1–101 (17%)
11–501 (17%)
51–2503 (50%)
1,001–5,0001 (17%)

Share of companies with a recorded size, by employees.

No size recorded: 1

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Frequently asked questions

About the Si21 data on this page.

How many companies use Si21?

Firmable holds confirmed Si21 detections for 7 distinct companies, 7 of them confirmed in the last 90 days. A company is counted once however many of its properties run it.

Which companies use Si21?

Vitruvian Partners, Housing Croatia and SoftNET are among the most prominent in the current set.

What industries use Si21?

Education and training, financial services and information technology and services lead the set, across 7 industries in total.

What size companies use Si21?

Adoption concentrates in the 51-250 employee band, across the companies whose size is recorded.

Where are Si21 users based?

Australia, Singapore, the United States and Indonesia account for most detections, across 9 countries.

How current is this data?

7 companies were confirmed in the last 90 days. Last detection 13 October 2026.

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