The most authoritative and relevant evidence comes from a direct SEC Form 4 filing accessed through the StockTitan platform, which details Jamie Dimon's insider sale of 69,512 JPMorgan Chase shares. SEC Form 4 filings are primary legal disclosures required for insider trades, making them highly reliable. While the exact dollar value of the sale depends on the transaction price, typical JPMorgan Chase share prices during the period of the sale indicate that the proceeds would be roughly $21 million, aligning closely with the claim. Additional corroboration from GuruFocus summaries of Dimon's trading activity further supports that such a sale took place recently. No credible evidence contradicts this, and unrelated articles mentioning Dimon are not relevant to this specific claim. The consistency between the reported share count and expected valuation leads to a high-confidence assessment that the claim is likely true.