Transparent oxide semiconductors face a fundamental challenge in achieving bipolar functionality due to inherent doping asymmetry. Spinel $\text{ZnG}{\text{a}}_2{\text{O}}_4$, traditionally $n$-type under oxygen-poor growth conditions, has recently been reported to exhibit $p$-type semiconductivity at elevated temperatures through the proposed formation of $\mathrm{Z}{\mathrm{n}}_{\mathrm{Ga}}$ antisite acceptors. In this work, we systematically reevaluate the feasibility of $p$-type semiconductivity in $\text{ZnG}{\text{a}}_2{\text{O}}_4$ by theoretically examining its electronic band structure and defect thermodynamics. The valence band maximum is primarily composed of deep and localized O $2p$ orbitals, severely impeding hole generation and transport. Furthermore, defect thermodynamics reveal a self-regulating compensation mechanism driven by cation antisites—$\mathrm{G}{\mathrm{a}}_{\mathrm{Zn}}$ donors and $\mathrm{Z}{\mathrm{n}}_{\mathrm{Ga}}$ acceptors. This mechanism intrinsically pins the Fermi level ($E_{\mathrm{F}}$) from mid-gap through the $n$-type region under all growth conditions. Crucially, $\mathrm{G}{\mathrm{a}}_{\mathrm{Zn}}$ donors exhibit negative formation energies across the $p$-type $E_{\mathrm{F}}$ range, triggering autocompensation that blocks extrinsic $p$-type doping. Experimental claims of high-temperature $p$-type behavior are undermined by inconsistencies in $E_{\mathrm{F}}$ measurements and unverified independently. Later proposed Zn-rich alloys $\left(\mathrm{Z}{\mathrm{n}}_{(1+2x)}\mathrm{G}{\mathrm{a}}_{2(1-x)}{\mathrm{O}}_4\right)$ with intermediate bands—intended to explain purported conductivity—are thermodynamically unstable ($\Delta H$ = −57.4 meV/atom) and exhibit unobserved sub-band-gap states. These findings confirm $\text{ZnG}{\text{a}}_2{\text{O}}_4$'s fundamental incompatibility with $p$-type functionality, necessitating rigorous experimental validation for viable $p$-type ultrawide band gap semiconductors.

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• Electrical conductivity
• Electronic structure
• First-principles calculations
• Point defects