As per Section 2.4.5 of the CDSL operating guidelines, partnership firms can open trading accounts in the name of the firm; however, demat accounts must be opened in the names of at least two authorised partners, with both the trading and demat accounts linked to the firm's PAN.

Since the Demat account is treated as a joint account (and not a non-individual account), the standard transmission procedure for joint holders will apply upon the death of one partner. To know more, see What is the procedure to claim shares after the death of a joint demat account holder? 
 
The surviving partners must open a new joint Demat account in the same sequence of names as in the existing account (excluding the deceased partner).

The following documents must be submitted to notify and claim the shares:

1. Duly filled Notifier form
2. Account Closure Form (PDF)
3. Transmission request form (PDF). To view the sample form, see (PDF)
4. The death certificate of the deceased partner—original, notarized, or attested by a gazetted officer.
5. Self-attested PAN copy of the surviving partners.
6. Self-attested copy of partner's Aadhar card, passport, driving license, or election card.
7. CMR hard copy of the surviving account holder (if DP is other than Jainam, then with the DP seal and signature).
8. Statement of holdings of account as of the date of submission of the transmission request.
9. New partnership deed.

Courier the documents to:
Jainam House
New Passport Office Road,
Kargil Chowk,
Piplod,
Surat-395007