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Not right now. You have just two choices in the market - Sell Steem for SBD or buy Steem with SBD.
Otherwise, we can power up Steem or transfer both Steem and SBD (including onto Poloniex).
It's so easy to move Steem and SBD to Poloniex, perhaps it's not really worth it to have an internal market that trades anything but SBD and Steem. That's my perspective, anyway. IMO, the current setup works nicely. No sense complicating it.

Yeah I know, but if we leave SBD, trading steem for btc on the internal market would possible yes?

Not as things stand now. That's a whole new ball of wax. It's beyond my tech grade, so I'm not sure what's involved. My guess is that it's not worth it, since you could just move them over to Polo and trade there for SBD, BTC or ETH.

Internal trading of btc could be very useful to the community here, but if there was a chance that it would discourage trading on bittrex and polo, then that would NOT be good for steem as it would be less visible to speculators who are not on the platform.