In some examples, a communication channel may be “shared,” which may allow users associated with two or more different groups (e.g., entities associated with two or more different organization and/or workspace identifiers) to join and participate in the data sharing through the communication channel. A shared communication channel may be public such that it is accessible to any user of groups associated with the shared communication channel, or may be private such that it is restricted to access by certain users or users having particular roles and/or types. A “shared communication channel” or an “externally shared communication channel” can enable two or more organizations, such as a first organization and a second organization to share data, exchange communications, and the like. In an example, the first organization and the second organization can be associated with different organization identifiers, can be associated with different business entities, have different tax identification numbers, and/or otherwise can be associated with different permissions such that users associated with the first organization and users associated with the second organization are not able to access data associated with the other organization, without the establishment of an externally shared channel. In some examples, a shared communication channel can be shared with one or more different workspaces and/or organizations that, without having a shared communication, would not otherwise have access to each other's data by the nature of the permission-based and/or group-based configuration of the communication platform described herein.