Network · AS21923

AS21923 CapitalSource Finance LLC

AS21923 (CapitalSource Finance LLC) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS21923

OwnerCapitalSource Finance LLC
KindInternet service provider
Servers, not peopleno
IPv4 addresses256
IPv4 ranges1
IPv6 ranges0

Risk score0

Nothing suspicious found.

Largest IPv4 ranges

12.150.170.0/24

Ranges and owner from DB-IP (CC BY 4.0), updated 2026-10-21.

Check an IP address →

Detect it in code

Spot AS21923 traffic at signup.

Send the visitor's IP. The response includes the ASN, the owner and flags.hosting.

curl https://veqen-app.com/v1/ip/check \
  -H "Authorization: Bearer $VEQEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"ip": "203.0.113.7"}'

import os, requests

r = requests.post(
    "https://veqen-app.com/v1/ip/check",
    headers={"Authorization": f"Bearer {os.environ['VEQEN_API_KEY']}"},
    json={"ip": "203.0.113.7"},
    timeout=10,
)
result = r.json()
print(result["risk"]["verdict"], result["risk"]["reasons"])

const res = await fetch("https://veqen-app.com/v1/ip/check", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.VEQEN_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({"ip": "203.0.113.7"}),
});
const result = await res.json();
console.log(result.risk.verdict, result.risk.reasons);

Questions

About AS21923

Is AS21923 a datacenter or VPN network?

AS21923 (CapitalSource Finance LLC) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS21923?

AS21923 is registered to CapitalSource Finance LLC. It announces about 256 IPv4 addresses.

How do I detect traffic from AS21923?

Call the Veqen IP check with the visitor's address. The response includes the ASN, the owner and whether the network is a datacenter, VPN network, relay or ISP.