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HubSpot Developer Changelog

Timeline API IDs must be globally unique

The Timeline API allows you to embed information from other applications directly into the HubSpot Timeline. It also enables marketers to create lists based on contacts that interacted with those Timeline Events.

What is it?

Each Timeline Event has an ID defined by the developer creating the events. Those events must be globally unique as specified in the documentation. Going forward, HubSpot will mandate unique ID’s  and will return an error when duplicate IDs are used for different CRM Objects.

Past Timeline Events that do not use Unique ID’s may have been removed or had properties removed from records. Any portals that are subject to data removal have been directly contacted. Going forward, all new events must follow the documentation and have Unique ID’s, or they will receive errors.

That error will look like:

Status code 400



“message”:”Event ID already in use, please choose a new unique ID”,



Why does it matter?

This change removes ambiguity that could potentially cause timeline events to appear on incorrect records.

When is this happening?

The v1 Timeline API will start returning errors for non-unique IDs on April 21st, 2021

If you have any questions or concerns about this update, please join the discussion in the community.