Hart's company, S&H Projects, invested in the lounge, which opened in July, 2008. Hart -- who's married to P!nk -- claims the Hard Rock hid profits and inflated expenses, thus denying S&H its fair share.
Hart's company claims the Hard Rock created the deception to mask some serious mismanagement problems with the hotel.
Wasted Space shut down last August. Hart's company wants unspecified damages.
The Hard Rock denies the allegations, and claims Wasted Space never made a dime in profits.