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List Tasks (Search)

POST https://api.copper.com/developer_api/v1/tasks/search

The /search endpoint provides the ability to list people and sort the results by certain parameters. When multiple criteria are provided, records meeting ALL criteria will be returned (the filtering criteria have an 'AND' relationship).

Certain fields can be filtered by an empty value, i.e., filter records where the field is not specified. For Tasks, these fields are: company, opportunity, city, state, postal_code, tags, custom dropdown, custom multi-select fields. Some fields (e.g. assignee_ids) can also filter for an empty value by specifying -2 as the ID.

To search by custom fields, see Search Entity by Custom Field.

Note that this endpoint is eligible to return computed custom field values, click here for more information.

To change the number of records returned, change the "page_size" parameter. E.g., specify 200 for a page size of 200 records. Please note that search requests are limited to returning only the first 100,000 records regardless of the pagination parameters. If your search filter matches more than 100,000 records, we recommend modifying your search filter to separate your result set.

Field Type Details Default
ids identifier[] An array of Task IDs. none
page_number number The page number (starting with 1) that you would like to view. 1
page_size number The number of entries included in a page of results 20
sort_by string The field on which to sort the results (see footnote 1). due_date
sort_direction string The direction in which to sort the results. Possible values are: asc or desc. asc
assignee_ids identifier[] The ids of Users that Tasks must be owned by, or -2 for Tasks with no owner. none
opportunity_ids identifier[] An array of Opportunity IDs (see footnote 2). none
project_ids identifier[] The ids of Projects that Tasks belong to, or -2 for Tasks with no project. none
statuses string[] Filter Tasks to statuses specified ("Open", "Completed"). none
tags string[] Filter Tasks to those that match at least one of the tags specified. none
followed number 1: followed, 2: not followed none
minimum_due_date timestamp The minimum due date Tasks must have. none
maximum_due_date timestamp The maximum due date Tasks must have. none
minimum_created_date timestamp The Unix timestamp of the earliest date Tasks are created. none
maximum_created_date timestamp The Unix timestamp of the latest date Tasks are created. none
minimum_modified_date timestamp The minimum modified date Tasks must have. none
maximum_modified_date timestamp The maximum modified date Tasks must have. none

Footnote:

  1. Possible fields are: name, assigned_to, related_to, status, priority, due_date, reminder_date, completed_date, date_created, date_modified.
  2. See List Opportunities (Search).

Request body

{
  "page_size": 25,
  "sort_by": "name"
}

Example Requests

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\"
}"
[
  {
    "id": 3726701,
    "name": "Demo Task",
    "related_resource": {
      "id": null,
      "type": null
    },
    "assignee_id": 137658,
    "due_date": null,
    "reminder_date": null,
    "completed_date": null,
    "priority": "None",
    "status": "Open",
    "details": null,
    "tags": [],
    "custom_fields": [],
    "date_created": 1496771985,
    "date_modified": 1496771985
  },
  {
    "id": 2277769,
    "name": "Download ProsperWorks Mobile App",
    "related_resource": {
      "id": 9607579,
      "type": "company"
    },
    "assignee_id": null,
    "due_date": null,
    "reminder_date": null,
    "completed_date": null,
    "priority": "None",
    "status": "Open",
    "details": "Visit the Google Play store or the Apple App store to download the ProsperWorks Android or iPhone app.",
    "tags": [],
    "custom_fields": [],
    "date_created": 1483988829,
    "date_modified": 1483989349
  },
  {
    "id": 2277771,
    "name": "Follow up Call (sample)",
    "related_resource": {
      "id": null,
      "type": null
    },
    "assignee_id": null,
    "due_date": 1483894800,
    "reminder_date": null,
    "completed_date": null,
    "priority": "None",
    "status": "Open",
    "details": null,
    "tags": [],
    "custom_fields": [],
    "date_created": 1483988829,
    "date_modified": 1489018922
  },
  {
    "id": 2277770,
    "name": "Follow up on Price Quote (sample)",
    "related_resource": {
      "id": null,
      "type": null
    },
    "assignee_id": null,
    "due_date": 1484067600,
    "reminder_date": null,
    "completed_date": null,
    "priority": "None",
    "status": "Open",
    "details": null,
    "tags": [],
    "custom_fields": [],
    "date_created": 1483988829,
    "date_modified": 1483988829
  },
  {
    "id": 3716920,
    "name": "My First Task",
    "related_resource": {
      "id": 144296,
      "type": "project"
    },
    "assignee_id": 137658,
    "due_date": 1496799000,
    "reminder_date": null,
    "completed_date": null,
    "priority": "None",
    "status": "Open",
    "details": "This is an update",
    "tags": [],
    "custom_fields": [],
    "date_created": 1496712856,
    "date_modified": 1496776369
  }
]

List Tasks in Groups of 200

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 200,
  \"sort_by\": \"name\"
}"
[
  {
    "id": 1,
    "name": "Download ProsperWorks Mobile App",
    "related_resource": {
      "id": 2,
      "type": "company"
    },
    "assignee_id": null,
    "due_date": 1516813200,
    "reminder_date": null,
    "completed_date": null,
    "priority": "None",
    "status": "Open",
    "details": "Visit the Google Play store or the Apple App store to download the ProsperWorks Android or iPhone app.",
    "tags": [],
    "custom_fields": [
      {
        "custom_field_definition_id": 6,
        "value": null
      },
      {
        "custom_field_definition_id": 12,
        "value": [
          9
        ]
      },
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1515434871,
    "date_modified": 1516824438,
    "custom_activity_type_id": 6
  },
  {
    "id": 3,
    "name": "Follow up Call (sample)",
    "related_resource": {
      "id": 5,
      "type": "person"
    },
    "assignee_id": null,
    "due_date": 1515776400,
    "reminder_date": null,
    "completed_date": null,
    "priority": "None",
    "status": "Open",
    "details": null,
    "tags": [],
    "custom_fields": [
      {
        "custom_field_definition_id": 6,
        "value": null
      },
      {
        "custom_field_definition_id": 12,
        "value": [
          9
        ]
      },
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1515434871,
    "date_modified": 1516824426,
    "custom_activity_type_id": 6
  },
  {
    "id": 2,
    "name": "Follow up on Price Quote (sample)",
    "related_resource": {
      "id": 4,
      "type": "opportunity"
    },
    "assignee_id": null,
    "due_date": 1515517200,
    "reminder_date": null,
    "completed_date": 1516822940,
    "priority": "None",
    "status": "Completed",
    "details": null,
    "tags": [],
    "custom_fields": [
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 12,
        "value": []
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 6,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1515434871,
    "date_modified": 1516822940,
    "custom_activity_type_id": 6
  },
  {
    "id": 6,
    "name": "New CRM Task",
    "related_resource": {
      "id": 1,
      "type": "project"
    },
    "assignee_id": 2,
    "due_date": 1516905000,
    "reminder_date": null,
    "completed_date": null,
    "priority": "High",
    "status": "Open",
    "details": null,
    "tags": [
      "tag1"
    ],
    "custom_fields": [
      {
        "custom_field_definition_id": 6,
        "value": 1515744000
      },
      {
        "custom_field_definition_id": 12,
        "value": [
          8
        ]
      },
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1516818999,
    "date_modified": 1516819000,
    "custom_activity_type_id": 6
  }
]

Search by Assignee Ids

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\",
  \"assignee_ids\": [2]
}"
[
  {
    "id": 6,
    "name": "New CRM Task",
    "related_resource": {
      "id": 1,
      "type": "project"
    },
    "assignee_id": 2,
    "due_date": 1516905000,
    "reminder_date": null,
    "completed_date": null,
    "priority": "High",
    "status": "Open",
    "details": null,
    "tags": [
      "tag1"
    ],
    "custom_fields": [
      {
        "custom_field_definition_id": 6,
        "value": 1515744000
      },
      {
        "custom_field_definition_id": 12,
        "value": [
          8
        ]
      },
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1516818999,
    "date_modified": 1516819000,
    "custom_activity_type_id": 6
  }
]

Search by Tags

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\",
  \"tags\": {
    \"option\": \"ANY\",
    \"value\": [\"tag1\"]
  }
}"
[
  {
    "id": 6,
    "name": "New CRM Task",
    "related_resource": {
      "id": 1,
      "type": "project"
    },
    "assignee_id": 2,
    "due_date": 1516905000,
    "reminder_date": null,
    "completed_date": null,
    "priority": "High",
    "status": "Open",
    "details": null,
    "tags": [
      "tag1"
    ],
    "custom_fields": [
      {
        "custom_field_definition_id": 6,
        "value": 1515744000
      },
      {
        "custom_field_definition_id": 12,
        "value": [
          8
        ]
      },
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1516818999,
    "date_modified": 1516819000,
    "custom_activity_type_id": 6
  }
]

Search by Followed

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\",
  \"followed\": 1
}"
[
  {
    "id": 6,
    "name": "New CRM Task",
    "related_resource": {
      "id": 1,
      "type": "project"
    },
    "assignee_id": 2,
    "due_date": 1516905000,
    "reminder_date": null,
    "completed_date": null,
    "priority": "High",
    "status": "Open",
    "details": null,
    "tags": [
      "tag1"
    ],
    "custom_fields": [
      {
        "custom_field_definition_id": 6,
        "value": 1515744000
      },
      {
        "custom_field_definition_id": 12,
        "value": [
          8
        ]
      },
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1516818999,
    "date_modified": 1516819000,
    "custom_activity_type_id": 6
  }
]

Search by Project Ids

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\",
  \"project_ids\": [1]
}"
[
  {
    "id": 6,
    "name": "New CRM Task",
    "related_resource": {
      "id": 1,
      "type": "project"
    },
    "assignee_id": 2,
    "due_date": 1516905000,
    "reminder_date": null,
    "completed_date": null,
    "priority": "High",
    "status": "Open",
    "details": null,
    "tags": [
      "tag1"
    ],
    "custom_fields": [
      {
        "custom_field_definition_id": 6,
        "value": 1515744000
      },
      {
        "custom_field_definition_id": 12,
        "value": [
          8
        ]
      },
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1516818999,
    "date_modified": 1516819000,
    "custom_activity_type_id": 6
  }
]

Search by Opportunity Ids

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\",
  \"project_ids\": [1]
}"
[
  {
    "id": 2,
    "name": "Follow up on Price Quote (sample)",
    "related_resource": {
      "id": 4,
      "type": "opportunity"
    },
    "assignee_id": null,
    "due_date": 1515517200,
    "reminder_date": null,
    "completed_date": null,
    "priority": "None",
    "status": "Open",
    "details": null,
    "tags": [],
    "custom_fields": [
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 12,
        "value": []
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 6,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1515434871,
    "date_modified": 1516820005,
    "custom_activity_type_id": 6
  }
]

Search by Statuses

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\",
  \"statuses\": [\"Completed\"]
}"
[
  {
    "id": 2,
    "name": "Follow up on Price Quote (sample)",
    "related_resource": {
      "id": 4,
      "type": "opportunity"
    },
    "assignee_id": null,
    "due_date": 1515517200,
    "reminder_date": null,
    "completed_date": 1516822940,
    "priority": "None",
    "status": "Completed",
    "details": null,
    "tags": [],
    "custom_fields": [
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 12,
        "value": []
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 6,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1515434871,
    "date_modified": 1516822940,
    "custom_activity_type_id": 6
  }
]

Search by Due Date

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\",
  \"minimum_due_date\": 1515764000,
  \"maximum_due_date\": 1515764000
}"
[
  {
    "id": 3,
    "name": "Follow up Call (sample)",
    "related_resource": {
      "id": 5,
      "type": "person"
    },
    "assignee_id": null,
    "due_date": 1515776400,
    "reminder_date": null,
    "completed_date": null,
    "priority": "None",
    "status": "Open",
    "details": null,
    "tags": [],
    "custom_fields": [
      {
        "custom_field_definition_id": 6,
        "value": null
      },
      {
        "custom_field_definition_id": 12,
        "value": [
          8
        ]
      },
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1515434871,
    "date_modified": 1516819079,
    "custom_activity_type_id": 6
  }
]

Search by Custom Date Field

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\",
  \"custom_fields\": [{
    \"custom_field_definition_id\": 6,
    \"minimum_value\": 1515744000,
    \"maximum_value\": 1515744000
  }]
}"
[
  {
    "id": 6,
    "name": "New CRM Task",
    "related_resource": {
      "id": 1,
      "type": "project"
    },
    "assignee_id": 2,
    "due_date": 1516905000,
    "reminder_date": null,
    "completed_date": null,
    "priority": "High",
    "status": "Open",
    "details": null,
    "tags": [
      "tag1"
    ],
    "custom_fields": [
      {
        "custom_field_definition_id": 6,
        "value": 1515744000
      },
      {
        "custom_field_definition_id": 12,
        "value": [
          8
        ]
      },
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1516818999,
    "date_modified": 1516819000,
    "custom_activity_type_id": 6
  }
]

Search by Multi-Select Dropdown

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\",
  \"custom_fields\": [{
    \"custom_field_definition_id\": 12,
    \"value\": [8],
    \"option\": \"ANY\"
  }]
}"
[
  {
    "id": 6,
    "name": "New CRM Task",
    "related_resource": {
      "id": 1,
      "type": "project"
    },
    "assignee_id": 2,
    "due_date": 1516905000,
    "reminder_date": null,
    "completed_date": null,
    "priority": "High",
    "status": "Open",
    "details": null,
    "tags": [
      "tag1"
    ],
    "custom_fields": [
      {
        "custom_field_definition_id": 6,
        "value": 1515744000
      },
      {
        "custom_field_definition_id": 12,
        "value": [
          8
        ]
      },
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1516818999,
    "date_modified": 1516819000,
    "custom_activity_type_id": 6
  }
]

Search by Multi-Select Dropdown Set to Empty

curl --location --request POST "https://api.copper.com/developer_api/v1/tasks/search" \
  --header "X-PW-AccessToken: YOUR_TOKEN_HERE" \
  --header "X-PW-Application: developer_api" \
  --header "X-PW-UserEmail: YOUR_EMAIL_HERE" \
  --header "Content-Type: application/json" \
  --data "{
  \"page_size\": 25,
  \"sort_by\": \"name\",
  \"custom_fields\": [{
    \"custom_field_definition_id\": 12,
    \"allow_empty\": true
  }]
}"
[
  {
    "id": 2,
    "name": "Follow up on Price Quote (sample)",
    "related_resource": {
      "id": 4,
      "type": "opportunity"
    },
    "assignee_id": null,
    "due_date": 1515517200,
    "reminder_date": null,
    "completed_date": 1516822940,
    "priority": "None",
    "status": "Completed",
    "details": null,
    "tags": [],
    "custom_fields": [
      {
        "custom_field_definition_id": 8,
        "value": null
      },
      {
        "custom_field_definition_id": 11,
        "value": null
      },
      {
        "custom_field_definition_id": 9,
        "value": null
      },
      {
        "custom_field_definition_id": 7,
        "value": false
      },
      {
        "custom_field_definition_id": 3,
        "value": null
      },
      {
        "custom_field_definition_id": 4,
        "value": null
      },
      {
        "custom_field_definition_id": 12,
        "value": []
      },
      {
        "custom_field_definition_id": 10,
        "value": null
      },
      {
        "custom_field_definition_id": 6,
        "value": null
      },
      {
        "custom_field_definition_id": 5,
        "value": null
      }
    ],
    "date_created": 1515434871,
    "date_modified": 1516822940,
    "custom_activity_type_id": 6
  }
]