... is solely or jointly entitled to the estate.

Jointly?
Ya, pada dasarnya frasa tanyaan berupaya menutup semua celah:

berhak merujuk ke hak tunggal atau sendirian.
turut mempunyai hak merujuk ke hak bersama (misalnya, anak-anak atas harta warisan orang tua).

Mohon acuan pendukungnya.
Silakan telusuri:

a-"solely or jointly entitled". Surjayanya akan mencakup a.l.:

http://www.dutchcivillaw.com/legislation/dcctitle2288.htm
...who are solely or jointly entitled to an amount of shares or depository receipts of ...


b-"entitled solely or jointly". Surjayanya akan meliputi a.l.:

https://www.legislation.nsw.gov.au/#/view/act/1898/4/full
Where a trustee entitled solely or jointly with another person to stock or ...