IQM Quantum Computers (Nasdaq: IQMX) has demonstrated simultaneous Greenberger–Horne–Zeilinger (GHZ) state entanglement across all 54 transmon qubits of its cloud-accessible IQM Emerald processor. The benchmark shows a raw (unmitigated) fidelity of 0.515 for 40 qubits and a readout-error-mitigated fidelity of 0.516 for the full 54-qubit chip, both just above the 0.500 threshold that separates genuine multipartite entanglement from separable noise. The processor uses a square lattice of 54 transmons with native two-qubit CZ gates enabled by tunable couplers, and the state preparation relied on an automated scheduling compiler that balances individual CZ gate fidelities against cumulative qubit idling times, cutting overall error rates by up to 50% alongside dynamical decoupling. The narrow fidelity margin highlights the steep scaling challenge of deep-circuit execution on unencoded physical QPUs and signals a need for further gate-speed optimizations and continuous calibration to prevent localized cross-talk. 1