E*TRADE from Morgan Stanley - Accounts API
E*TRADE from Morgan Stanley operates a genuinely public, self-service developer platform whose REST Accounts API gives an authenticated E*TRADE user's authorized application access to detailed account information: the account list, cash and margin balances, portfolio positions, and transaction history. It is a versioned (V1) REST API documented with Swagger inside the portal, authenticated with OAuth 1.0a (request token, user authorization, access token, renewal, and revocation), and backed by a full sandbox environment (apisb.etrade.com) for testing before hitting the production host (api.etrade.com). This is the retail-brokerage arm of the Morgan Stanley umbrella and, unlike the institutional API Platform, its docs and sandbox are openly reachable to any developer who registers for a consumer/sandbox key.