Source Attribution Policy

Stadar normalises esports data from a number of upstream sources. Each source has its own licence and its own attribution expectations. This policy tells you which sources feed which fields, how you can identify them in each API response, and what you must do when you re-display or redistribute the data.

1. The _sources block

Every API response includes a _sources array under meta. Each entry names the source, the licence it ships under, and the canonical URL of the upstream page where applicable. This block is the authoritative attribution surface — treat it as part of the payload, not as decoration.

{
  "meta": {
    "_sources": [
      {
        "name": "Liquipedia",
        "license": "CC-BY-SA-3.0",
        "url": "https://liquipedia.net/leagueoflegends/LCK/2026/Spring"
      },
      {
        "name": "Riot LoL Esports API",
        "license": "Riot API ToS",
        "url": "https://esports-api.lolesports.com"
      }
    ]
  }
}

2. Liquipedia (CC-BY-SA 3.0)

Liquipedia powers our tournament structure, bracket and group-stage data, rosters and lineup history, prize-pool figures, and most descriptive metadata across all games. Liquipedia's content is licensed under Creative Commons Attribution-ShareAlike 3.0 (CC-BY-SA 3.0). When you re-display or redistribute Liquipedia-derived content you must:

credit "Liquipedia contributors" with a link to the canonical Liquipedia URL from the _sources entry, in a way visible to the end user of the surface where the content appears;
name the licence as CC-BY-SA 3.0 and link to it;
indicate that the content has been adapted (because Stadar normalises and re-shapes it); and
licence any substantial republication of the Liquipedia-derived portion of your work under CC-BY-SA 3.0 (or a compatible licence). This is the share-alike obligation — it travels with the content, not with Stadar.

"Substantial" in this context means a republication that a reasonable person would recognise as a re-creation of the upstream Liquipedia article, page, or bracket. Using a single roster row or a match-score number alongside your own narrative is normal informational use; mirroring an entire Liquipedia bracket page into your product is substantial. If you're unsure, the safe default is to publish the affected surface under CC-BY-SA 3.0.

3. Riot LoL Esports API

League of Legends professional match data — schedule, live state, MVP and event signal — is supplemented from Riot's LoL Esports API under Riot's API Terms of Service. You must observe Riot's Legal Jibber Jabber and developer policies for any product incorporating this data; Stadar relays the source identification in the _sources block. Where Riot requires that you credit Riot Games as the data source, do so.

4. OpenDota

Dota 2 match details are supplemented from OpenDota, an open-source community project that re-exposes Valve's match-history data. OpenDota content is freely usable; we ask that you credit OpenDota in the same place you credit Liquipedia when OpenDota appears in the _sources block.

5. Tournament-organiser pages and bo3.gg

Some fixtures and live results are sourced from tournament organisers' public pages and from bo3.gg under a courtesy arrangement. These appear in the _sources block with the organiser's name and the canonical page URL. Credit the named source when you re-display content derived from it.

6. Practical guidance

You don't need to surface attribution on every UI element. A footer credit, an "information" affordance, an about page, or a per-page "Sources" disclosure are all acceptable, provided the credit is reasonable for the medium and a viewer who looks can identify the source. The two things that are never acceptable are stripping the _sources block from cached responses and republishing Liquipedia content under a more restrictive licence than CC-BY-SA 3.0.

7. Questions and disputes

If a rightsholder believes Stadar or a downstream user has not honoured an attribution obligation, email [email protected] with "Attribution" in the subject line. We respond within five business days and will work in good faith to resolve the issue, including by removing the affected source from future responses if asked.

Attribution Policy.