"I appreciate you saying thank you for taking your question, but I'm not going to answer your question because you already know everything about my company," Goncalves said.
The CEO said during the public call that he was "going to take the next question" because Dubinsky had given Cliffs a $4 price target and because "you think that we can't sell assets."
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This was Goncalves' first investor conference call since becoming CEO in early August.
As a senior equity analyst covering metals and mining for Wells Fargo, Dubinsky researches companies and publishes recommendations about the future of stocks.
Well Fargo and Dubinsky downgraded Cliffs in March and lowered the valuation range to $4 to $7 from a previous range of $7 to $10 in October.
"We continue to rate CLF shares at 'underperform' as we see iron ore pricing remaining under pressure for the foreseeable future," wrote Dubinsky in a note to clients in September.