Stock Monitor does not collect, store, or share any personal data. All settings — tracked symbols, portfolio, appearance and preferences — are stored only locally in your browser (WebExtensions storage API) and never leave your device. The extension makes network requests only to the public Yahoo Finance API (query1.finance.yahoo.com and query2.finance.yahoo.com) to retrieve public market price data for the symbols you choose to track; these requests are sent without cookies (credentials omitted). There is no analytics, no tracking, no advertising, and no transmission of data to the developer or any third party. Declared data collection: none.