Yes, it would take a broker that would accept shorts on penny stocks. I don't know of any. Call your own broker and ask. And again, it doesn't make sense to even do it. You'd have more in margin to put up as collateral than you could EVER make doing it, IF you were successful. If not successful, you stand to lose your margin.
For penny stocks, it is far simpler to just buy on dips and sell on peaks. Betting money that a penny stock will drop 10% is silly - it is just as likely to rise 10%.
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