Hi Mark,
The filter you are using are documented here:
https://docs.reltio.com/entitiesapi/entitiesfiltering.html. These are used to return entities that meet the attribute filters. I don't believe there is a way to filter within an individual entity using the API, like you are trying to do. But you may need support to confirm that.
Assuming the above is correct, you may want to set up your own API. That API would call the Reltio API, parse the return using
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse or similar functionality and returns the part of the response that you want to the caller.
You may also wish to add an enhancement request using the Aha! portal. If you don't have access to that, please check with your customer success manager.
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Gino Fortunato
Senior Solution Engineer
Reltio
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