# OATI WebCARES Root CA root certificate (OATI)

> OATI WebCARES Root CA is a root CA certificate operated by OATI (RSA 4096, valid until 2038-06-03, SHA-256 7A77C6C6). As of the latest CCADB data it is trusted for TLS server authentication by 1 of 4 major root stores: Microsoft.

Source: https://ssl.sh/roots/oati-webcares-root-ca/
Last updated: 2026-11-10

OATI WebCARES Root CA is a root CA certificate operated by OATI (RSA 4096, valid until 2038-06-03, SHA-256 7A77C6C6). As of the latest CCADB data it is trusted for TLS server authentication by 1 of 4 major root stores: Microsoft.

| Field | Value |
|---|---|
| CA owner | OATI |
| Subject | CN=OATI WebCARES Root CA,O=Open Access Technology International Inc,L=Minneapolis,ST=MN,C=US |
| SHA-256 | 7A77C6C61EEEB9AA65C4EA410D65D895B26A81123283009DB104B48DE80B2479 |
| SPKI SHA-256 | 8E15D426CD04898F218BE2E5FE3784F375094CC435DC61AD86C4A3C01511DBE1 |
| Valid from | 2008-06-03 |
| Expires | 2038-06-03 |
| Key | RSA 4096 |
| Signature algorithm | sha1WithRSAEncryption |
| Serial number | 25762066A7560874F9004BFA1C82841 |
| SHA-1 (Windows thumbprint) | 4B6BD2D3884E46C80CE2B962BC598CD9D5D84013 |

## Root store status

| Root store | Status | Trusted for TLS | Distrust for TLS after | Details |
|---|---|---|---|---|
| Chrome | Not included | No | - | - |
| Mozilla | Not included | No | - | - |
| Apple | Not included | No | - | - |
| Microsoft | Included | Yes | - | Trusted EKUs: Server Authentication, Client Authentication, Secure Email; Not-before cutoff: 2026-05-19 (Secure Email) |

The CCADB lists no EV policy OID for OATI WebCARES Root CA.

## Intermediate CAs issued by this root

The CCADB lists 5 intermediate CA certificates signed directly by OATI WebCARES Root CA: 3 currently valid, 2 expired and 0 revoked (revoked includes those whose parent was revoked).

| Intermediate | Operated by | Expires | Status | SHA-256 |
|---|---|---|---|---|
| webCARES Client Issuing CA 2025 | Open Access Technology International, Inc. (OATI) | 2030-10-09 | Valid | E667D663E345CC5D2F067BD4AA314B8C248E783B2505B2F133B448B65724F368 |
| webCARES Server Issuing CA 2025 | Open Access Technology International, Inc. (OATI) | 2030-10-09 | Valid | 3A29FE00B8357BD72271531BDA2FB74D702C657E30E4A73B2299A5DA3FB02738 |
| webCARES Issuing CA 2021 | Open Access Technology International, Inc. (OATI) | 2027-03-25 | Valid | C4F20BAEC41F2357D25EC91FC62F41C642CA68281F7A21D333CE9522CFD9AD3A |
| webCARES Issuing CA 2017 | Open Access Technology International, Inc. (OATI) | 2023-08-07 | Expired | C8A2F18BDEA4B7A17EDC369BAB52A6992807C0BEE936F7F63A9191957279C57C |
| webCARES Issuing CA 2013 | Open Access Technology International, Inc. (OATI) | 2019-10-28 | Expired | 8D998FCED07468C7D46624768CB71F5ACFA32C8180829F20585D801AF2E98003 |

## Cross-signed versions

No certificate in the CCADB has the same subject and public key as OATI WebCARES Root CA with a different issuer, so a client has to carry OATI WebCARES Root CA itself in its root store to trust it.


## What happens when it expires

OATI WebCARES Root CA is valid until 2038-06-03, about 11.6 years after this data snapshot (2026-11-10). From that day, browsers and operating systems that check trust-anchor expiry stop accepting chains that end at this root, so any certificate that can only chain to it fails validation. Android is a known exception: it does not enforce the expiry date of trust anchors.

## FAQ

**Is OATI WebCARES Root CA trusted by Chrome, Firefox, Safari and Windows?**

As of 2026-11-10, Microsoft trust it for TLS server authentication; Chrome, Mozilla, Apple do not.

**When does OATI WebCARES Root CA expire?**

On 2038-06-03, about 11.6 years after the 2026-11-10 data snapshot.

**How many intermediate certificates has OATI WebCARES Root CA issued?**

The CCADB lists 5: 3 valid, 2 expired and 0 revoked. The newest valid one is webCARES Client Issuing CA 2025, valid until 2030-10-09.

**Is OATI WebCARES Root CA cross-signed?**

No. The CCADB has no certificate with the same subject and public key signed by another CA.

Sources: CCADB TLS Server Authentication report, All Included Root Certificate Trust Bit Settings, All Certificate Information (V5), the per-store TLS reports and Mozilla's Included CA Certificate Report (ccadb.org/resources).