Canadian aquaculture group Cooke Inc argues its $1.04 billion takeover proposal for Tasmanian salmon farmer Tassal offers a decent premium because Tasmanian government restrictions on granting new marine leases are helping to bolster salmon volumes at the target company.

Tassal has rejected its third buyout proposal from Cooke in a month and is refusing to engage in talks. It says the $4.85 per share price undervalues the group even though it was at a 22 per cent premium to the closing price of $3.97 before the proposal became public.