Protection of bona fide transferees preserves valid title against trust claims when transfer occurred for consideration without notice. A bona fide transferee for consideration who takes trust property without notice acquires enforceable rights that a beneficiary cannot defeat; this protection is measured at the time purchase-money is paid or the conveyance executed and also covers subsequent transferees who obtain from such purchasers. The rule excludes judgment-creditors who attach and purchase trust property, preserves the status of money and negotiable instruments in circulation held by bona fide holders, and does not affect established principles governing transferred debts or charges.