The REST Order Entry API (OE API) is an easy-to-use service designed to meet the needs of clients trading non-latency-sensitive programmatic strategies. The REST OE API is an extended offering of CME Direct capabilities, CME Group's multi-venue front-end with access to CME Globex and CME ClearPort. REST OE API offers low-cost programmatic access to CME Globex leveraging CME Direct policies and procedures.
Currently, API access to CME Globex markets is available via the CME iLink FIX service. The REST OE API provides a complementary service, with API access to markets via RESTful Web Service APIs using JSON messaging.
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- The Order Management and User-Defined Instrument APIs are limited to 10 calls per second for each API clientID.
- The Order Management and API is limited to 50 total concurrent requests. The Query Status API is limited to 50 20 total concurrent requests.
- Any call that exceeds these limits will result in a Response Code 429.
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