Access control for a document management and collaboration system

A system, comprising:

• one or more processors;
• and
• memory that includes instructions that, as a result of execution by the one or more processors, cause the system to:
• receive a request to expand privileges for accessing a particular document, the privileges enabling access to the particular document and the particular document maintained by the system by at least:
• determining a set of privileges for a set of user devices for accessing the particular document;
• obtaining a calculated similarity measure associated with the particular document and the set of user devices, wherein the similarity measurement indicates interest by the set of user devices in the particular document;
• transmitting an approval request of the set of privileges to a particular user device having privileges to approve access to the particular document in accordance with the similarity measure indicated by an access control policy associated with the particular document;
• receiving a response to the approval request;
• and
• applying the set of privileges to the set of user devices to access the particular document.

A non-transitory computer-readable storage medium having stored thereon executable instructions that, as a result of being executed by one or more processors of a computer system, cause the computer system to at least:

• receive an access control policy specifying that expanding privileges of one or more users for accessing at least one document maintained by a document management and collaboration system by a first user is performed based at least in part on a calculated similarity measure between the at least one document and the one or more users, wherein the similarity measure indicates interest by the one or more users in the at least one document;
• modify a user interface displayed to the first user to display a request to expand the privileges of the one or more users;
• and
• in response to the request, based at least in part on the access control policy, set the privileges of the one or more users to a privilege level specified by the first user through the user interface.