{"schema_version":"secwatch.filing_event.v1","accession":"0001193125-26-371263","form_type":"8-K","ticker":"ETCG","cik":"0001705181","company_name":"Grayscale Ethereum Classic Trust (ETC)","filed_at":"2026-08-27T20:06:02+00:00","discovered_at":"2026-08-27T20:07:09.636264+00:00","generated_at":"2026-08-27T20:08:07.769490+00:00","sec_items":["8.01"],"event_type":"other_material","sentiment":"neutral","materiality_score":0.3,"calibrated_materiality_score":0.3,"confidence":"high","headline":"Grayscale Ethereum Classic Trust to adopt new CoinDesk benchmark index for NAV from Sept 1, 2026","bullets":["Effective Sept 1, 2026, NAV uses CoinDesk Ethereum Classic Benchmark Extended Rate, replacing Price Index.","New index methodology includes volume weighting, outlier detection, inactivity adjustments, and manipulation resistance.","Index provider can adjust methodology without consent; sponsor may use cascading fallback indices if unavailable.","Change affects only NAV calculation; underlying ETC holdings and operational structure remain unchanged."],"urls":{"canonical":"https://secwatch.observer/filing/0001193125-26-371263","json":"https://secwatch.observer/filing/0001193125-26-371263.json","markdown":"https://secwatch.observer/filing/0001193125-26-371263.md","text":"https://secwatch.observer/filing/0001193125-26-371263.txt","edgar_index":"https://www.sec.gov/Archives/edgar/data/1705181/000119312526371263/0001193125-26-371263-index.htm","edgar_primary_document":"https://www.sec.gov/Archives/edgar/data/1705181/000119312526371263/etcg-20260827.htm"},"model":{"generated_by":"deepseek-v4-flash:cloud@v2","generated_at":"2026-08-27T20:08:07.769490+00:00"},"review":{"review_status":"machine_generated","human_reviewed":false,"corrected":false,"correction_note":null,"correction_timestamp":null,"superseded_by":null,"related_filings":[]},"source_grounded_claims":[],"license":"Source filings: public domain (SEC EDGAR). Summaries (headline + bullets): CC-BY-4.0; attribute https://secwatch.observer"}