Visit Eikon COM APIs page on this portal where you can find documentation, code samples and tutorials. Here's the link to Eikon APIs family. From this page click on "COM APIs for use in Microsoft Office" or "COM APIs for use in custom applications" depending on whether you want to use Eikon COM API libraries in Excel or you want to build custom applications using these APIs.
https://developers.refinitiv.com/en/eikon-apis-0/apis-in-this-family

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