This document provides a justification to the OGC Technical Committee (TC) for consideration of STAC API as a Community standard. This justification, along with the submitted candidate Community standard, will form the basis for TC review and vote to approve the start of a Work Item as the first step in the Community standard process for this standard.

The submitters agree to abide by the TC Policies and Procedures and OGC Intellectual Property Rights Policy (http://www.opengeospatial.org/ogc/policies) during the processing of this submission.

Once approved, the Community standard Work Item defined by this document is valid for six (6) months.

The SpatioTemporal Asset Catalog (STAC) is an open specification designed to improve the discovery, accessibility, and interoperability of geospatial data. The STAC API is the dynamic endpoint conforming to OGC API - Features described using the OpenAPI Version 3.x specifications

The STAC API specification supports geospatial interoperability requirements by providing a common metadata framework to expose geospatial assets, such as satellite imagery and other spatiotemporal raster data. Interoperability eases the search process and enables users to find and use data in various formats provided by multiple technology providers.

The STAC API specification evolved from different organizations' collaborative efforts to increase the interoperability of searching for and using satellite imagery. The development of the STAC API was driven by the need to overcome the challenges associated with different tools, APIs, and data formats provided for and used by the geospatial community.

The primary STAC use case is to simplify the finding and use of geospatial assets. It is beneficial for data providers, developers, and data users. Providers can more easily expose their data to the world, developers have a standardized way to interact with geospatial data, and users can more easily find and ingest the data they need.

To foster uptake and use of the STAC specification and API, the STAC community provides various free and open tools and resources that facilitate its use. These include an HTML-based browser for accessing STAC catalogs and a STAC-compliant Web API for searching and serving metadata for geospatial data.

The STAC specification implements and extends the OGC API – Features standard, and many datasets have been described using the specification. STAC and OGC API - Features evolved together and continually aligned based on user feedback and new implementations.

In addition to the OGC API - Features, the STAC dynamic catalogs align well with the draft OGC API - Records standard. Multiple development sprints have been completed with OGC members to ensure alignment between STAC and the OGC Standards baseline.

The STAC specification fits well within the OGC API roadmap and aligns with the OGC API - Features. The STAC API also attempts to align with the draft OGC API - Records Standard (currently in work).

The STAC specification enhances OGC operations and community involvement by describing geospatial data to newer, non-geospatial companies.

The following is a list of publically available implementations of the STAC API specification.

Microsoft Planetary Computer - https://planetarycomputer.microsoft.com/api/stac/v1 Element84 Earthsearch - https://earth-search.aws.element84.com/v1/ OpenEO - https://openeo.eodc.eu/v1.0/ Google Earth Engine - https://gee.stac.cloud/?t=catalogs USGS Landsat - https://landsatlook.usgs.gov/stac-server/

Date of most recent version:

Version 1.0.0 of the STAC API Spec was released on Apr 25, 2023

Implementation description:

Dynamic STAC catalogs and APIs enhance the static STAC specification ("stac-spec") by offering real-time query responses, unlike static catalogs that are crawled and don’t interact with queries. These dynamic systems, reliant on servers, databases, and clusters, provide a robust and interactive way to access geospatial assets. While this increases maintenance, the dynamic approach aligns well with the OGC API roadmap, particularly with OGC API - Features and OGC API – Records. This integration offers improved functionality and accessibility in managing and querying geospatial data, making dynamic STAC a valuable addition to the geospatial community.

The STAC API specification is composed of three foundational smaller, individual specifications.

The last, Item Search, can be composed of different Extensions to help customize a full STAC API implementation. The JSON schema files describing the specification form the reference API and are rendered online using HTML and human-readable documentation. STAC APIs are described by the OpenAPI specification and provide data as JSON and Geo-JSON for machine consumption.

A STAC API can be implemented in compliance with the OGC API - Features Standard. The STAC specification enhances OGC operations and community involvement by describing geospatial in an easy to consume and understand manner, enabling non-geospatial parties to access and use STAC-compliant catalogs.

Implementation URL: https://api.stacspec.org/v1.0.0/

Is implementation complete?

If not, what portions of the proposed Community standard are implemented?

Is the proposed Community standard currently publicly available?

URL: https://www.stacspec.com

Sparkgeo Element84 Planet Labs Microsoft WWU Münster EURAC

Will the contributor retain intellectual property rights?

If yes, the contributor will be required to work with OGC staff to properly attribute the submitter’s intellectual property rights.

If no, the contributor will assign intellectual property rights to the OGC.