कर्त्ता becomes कर्म-like when the usual meaning has the syntactical कर्त्ता acting as कर्म. For example, lady cooks the soup - has lady as कर्त्ता and soup as कर्म. In the sentence "the soup cooks by itself", soup is कर्त्ता syntactically but it is कर्म in the usual sense. This case has the following implications:
1. भावर्कर्मणोः - आत्मनेपद
2. सार्वधातुके यक् - यक्
3. चिण् भावकर्मणोः - चिण्
4. स्यसिच् सीयुट् - चिण्वद्भाव