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I recently downloaded Zerodha''s application form. I came across
a) running account authorization page, wherein it was mentioned that securities will be retained by them unless we instruct to transfer the same to our A/c. Also securities A/c will be settled once monthly/quarterly &
b)All Securities shall be subject to lien

Query

a)When payment has to be made upfront why should securities be retained by them &
b)Securities being subject to lien is being done only by Zerodha (at least not being done by its nearest competitor)

Request somebody to please clarify on the same