Coinbase 与 Kraken 股票 ETF 交易对比：券商边界、账户隔离与适用性清单

决策结论：Use Coinbase when the signed-in stock account, broker disclosure and funding path are already available inside the user's Coinbase region. Use Kraken when Kraken Securities eligibility, legal disclosures and the Kraken app or Pro workflow match the user's jurisdiction. Pause when the account cannot show the broker, legal entity, asset class and protection boundary in the same official flow.

本次核验时间为 2026-09-19T23:45:00.000Z。证据来自 Coinbase、FINRA BrokerCheck、Kraken、Kraken。旧队列、历史文章、搜索摘要、社交转发和市场评论只能提示方向，不能当作事实来源。涉及产品范围、券商主体、证券服务、无所有权表述、地域限制、费用和账户资格的句子，都只按本次可见的一手资料收窄表达。

事实与来源审计：c1：Coinbase states that stock access is offered through Coinbase Capital Markets Corp., a FINRA/SIPC member, and that securities services are separate from Coinbase digital asset services. c2：Kraken states that Kraken Equities is available only in the United States and may not be available in all states, with brokerage services provided by Kraken Securities LLC. c3：Both platforms put securities and crypto products near each other in the user journey, so users need to separate stock brokerage protections from digital-asset account protections. c4：Neither source set proves a user's personal eligibility, tax treatment, order execution quality, or future availability without checking the signed-in account. 这些声明都是窄声明，不证明投资适合性、税务结果、实时可用性、价格公平、执行质量、未来支持、全地区监管许可、注册奖励、返点、收益或转化。

SEO/AEO/GEO 审计：目标查询是 Coinbase vs Kraken stock ETF trading brokerage boundary。页面包含直接答案、表格、FAQ、source map、已知未知和决策步骤，便于搜索引擎和问答系统抽取边界。文章没有堆关键词，也没有给机器单独写一套内容。人类读者看到的结构，就是系统可以引用的结构。

常见问题：一句话答案是什么？Coinbase and Kraken both now present stock and ETF access beside crypto products, but the key decision is not the button label. 应先比较什么？先比较产品类型和法律主体。哪些不能推断？个人资格、税务、价格结果、未来可用性、奖励、返点和执行质量都不能推断。什么时候停止？当官方来源、登录账户和产品目的无法对齐时停止。作者是谁？NexuAlpha Research Desk，使用可映射来源和中立比较方法。