| Group | Title | Most stable | In progress | URL Form 1 | URL1 Result | URL Form 2 | URL2 Result |
| App | SAMP - Simple Application Messaging Protocol | 1.3 | | URL | latest REC, but redirects to documents/SAMP/ | URL | |
| VOTable - VOTable Format Definition | 1.4 | | URL | REC for 1.3, not 1.4 | | |
| MOC - HEALPix Multi-Order Coverage Map | 1.1 | | URL | 404 Not Found | | |
| HiPS - Hierarchical Progressive Survey | 1.0 | | URL | 404 Not Found | | |
| DAL | DALI - Data Access Layer Interface | 1.1 | | URL | 404 Not Found | | |
| DataLink | 1.0 | | URL | 404 Not Found | | |
| Simple Cone Search | 1.03 | 1.1 | URL | latest REC | | |
| SIA - Simple Image Access | 2.0 | | URL | REC for 1.0, not 2.0 | | |
| SLAP - Simple Line Access | 1.0 | 2.0 | URL | latest REC | | |
| SSA - Simple Spectral Access | 1.1 | | URL | latest REC | | |
| STC-S: Space-Time Coordinate Metadata Linear String Implementation | 1.0 | | URL | Confusing: Points to a note from 2007. Doc page points to a WD from 2013. | | |
| TAP - Table Access Protocol | 1.1 | | URL | WD 1.0 from 2009 instead of REC 1.1 from 2019 | | |
| TAPRegExt - A VOResource Schema Extension for Describing TAP Services | 1.0 | | URL | 404 Not Found | | |
| ADQL) and its string representation, ADQL/s.">ADQL - Astronomical Data Query Language | 2.00 | 2.1 | URL | latest REC | | |
| SimDAL - Simulation Data Access Layer | 1.0 | | URL | 404 Not Found | | |
| VOEvent Transport Protocol | 2.00 | | URL | Note 1.0 from 2009 instead of REC 2.0 from 2017 | | |
| SODA - Server-side Operations for Data Access | 1.0 | | URL | 404 Not Found | | |
| Object Visibility Simple Access Protocol | | 1.0 | URL | 404 Not Found | | |
| EPN-TAP: Publishing Solar System Data to the Virtual Observatory | | 2.0 | URL | 404 Not Found | | |
| DaM | PHOTDM - Photometry Data Model | 1.0 | | URL | 404 Not Found | | |
| SimDM - Simulation Data Model | 1.0 | | URL | 404 Not Found | | |
| STC) metadata for the Virtual Observatory.">STC - Space-Time Coordinate Metadata for the Virtual Observatory | 1.33 | | URL | latest REC | | |
| Data Model for Astronomical DataSet Characterisation | 1.13 | | URL | latest REC | | |
| SSLDM - Simple Spectral Lines Data Model | 1.0 | RFC | URL | 404 Not Found | | |
| SpectralDM - IVOA Spectral Data Model | 1.1 | | URL | 404 Not Found | | |
| ObsCore - Observation Data Model Core Components and its Implementation in the Table Access Protocol | 1.1 | | URL | 404 Not Found | | |
| VODML - A Consistent Modeling Language for IVOA Data Models | 1.0 | | URL | 404 Not Found | | |
| DatasetDM - Dataset Metadata Model | | 1.0 | URL | 404 Not Found | | |
| CubeDM - N-Dimensional Cube/Image Model | | 1.0 | URL | 404 Not Found | | |
| ProvenanceDM - Provenance Data Model | 1.0 | 1.0 | URL | 404 Not Found | | |
| Astronomical Coordinates and Coordinate Systems | | RFC | URL | 404 Not Found | | |
| WCS Transform Model | | 1.0 | URL | 404 Not Found | | |
| Meas - Astronomical Measurements Model | | RFC | URL | 404 Not Found | | |
| Observation Locator Table Access Protocol | | RFC | URL | 404 Not Found | | |
| GWS | PDL - Parameter Description Language | 1.0 | | URL | 404 Not Found | | |
| SSO - Single-Sign-On Profile: Authentication Mechanisms | 2.0 | | URL | 404 Not Found | | |
| VOSpace service specification | 2.1 | | URL | WD 2.1 from 2014 instead of REC 2.1 from 2018 | | |
| Credential Delegation Protocol | 1.0 | | URL | | | |
| UWS - Universal Worker Service | 1.1 | | URL | | | |
| VOSI - IVOA Support Interfaces | 1.1 | | URL | | | |
| GMS - Group Membership Service | | 1.0 | URL | | | |
| ReR | IVOA Identifiers | 2.0 | | URL | | | |
| IVOA Registry Interfaces | 1.1 | | URL | | | |
| RM - Resource Metadata for the Virtual Observatory | 1.12 | | URL | | | |
| StandardsRegExt: a VOResource Schema Extension for Describing IVOA Standards | 1.0 | | URL | | | |
| SimpleDALRegExt - Describing Simple Data Access Services | 1.1 | 1.2 | URL | | | |
| VOResource - an XML Encoding Schema for Resource Metadata | 1.1 | | URL | | | |
| VODataService - A VOResource Schema Extension for Describing Collections and Services | 1.1 | 1.2 | URL | | | |
| RegTAP - Registry Relational Schema | 1.1 | | URL | | | |
| Semantics | VOUnits - Units in the VO | 1.0 | | URL | | | |
| UCD - An IVOA standard for Unified Content Descriptors | 1.10 | | URL | | | |
UCD1+ Controlled Vocabulary version <= 1.3: recommendation Version >= 1.4: endorsed note | 1.3 | 1.4 | URL | | | |
| Maintenance of the list of UCD words | 1.20 | RFC | URL | | | |
| Vocabularies in the Virtual Observatory | 1.19 | 2.00 | URL | | | |
| SDP | DocStd - IVOA Document Standards | 2.0 | | URL | | | |
| VOE | OpenSkyNode, part of the OpenSkyQuery Portal">VOEvent - Sky Event Reporting Metadata (VOEvent) | 2.0 | | URL | | | |
| VOEventRegExt - An XML Encoding Schema for Resource Metatdata for Collections of Events | | 1.0 | URL | | | |