Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance

Indicates whether an object is signed by a specified certificate or asymmetric key.

Transact-SQL syntax conventions


'OBJECT', @object_id, @class, @thumbprint  


To view Transact-SQL syntax for SQL Server 2014 and earlier, see Previous versions documentation.


The type of securable class.

The object_id of the object being tested. @object_id is type int.

The class of the object:

  • 'certificate'

  • 'asymmetric key'

@class is sysname.

The SHA thumbprint of the object. @thumbprint is type varbinary(32).

Returned Types



IS_OBJECTSIGNED returns the following values.

Return value Description
NULL The object is not signed, or the object is not valid.
0 The object is signed, but the signature is not valid.
1 The object is signed.


Requires VIEW DEFINITION on the certificate or asymmetric key.


A. Displaying extended properties on a database

The following example tests if the spt_fallback_db table in the master database is signed by the schema signing certificate.

USE master;  
-- Declare a variable to hold a thumbprint and an object name  
DECLARE @thumbprint varbinary(20), @objectname sysname;  
-- Populate the thumbprint variable with the thumbprint of   
-- the master database schema signing certificate  
SELECT @thumbprint = thumbprint   
FROM sys.certificates   
WHERE name LIKE '%SchemaSigningCertificate%';  
-- Populate the object name variable with a table name in master  
SELECT @objectname = 'spt_fallback_db';  
-- Query to see if the table is signed by the thumbprint  
SELECT @objectname AS [object name],  
'OBJECT', OBJECT_ID(@objectname), 'certificate', @thumbprint  
) AS [Is the object signed?] ;  

See Also

sys.fn_check_object_signatures (Transact-SQL)