Siebel Developer's Reference > Business Component User Properties > Controlling Records >

Disabling Modifications to Saved Records

The No Change Field n user property disallows modifying a field value after Siebel CRM saves the record. It must specify the name of a business component field, not enclosed in quotes.

You can specify this user property with or without the numeric suffix. For more information, see Numbering Instances of a User Property.

You can configure Siebel CRM to modify the value for this user property, create a new instance of it, or deactivate it.