If the portfolio mainly represents cash and receivable debts, its units also represent cash and debt rather than tangible assets.
Therefore, these units cannot be freely bought and sold in a secondary market at changing prices. The source presents a Murabahah fund as a closed-end structure whose units are not negotiable like asset-backed fund units.
Opening interactive controls...
Murabahah Funds, Sale of Debt (بيع الدين) and Mixed Funds
If the portfolio mainly represents cash and receivable debts, its units also represent cash and debt rather than tangible assets.
Therefore, these units cannot be freely bought and sold in a secondary market at changing prices. The source presents a Murabahah fund as a closed-end structure whose units are not negotiable like asset-backed fund units.