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Yes. Pc (Collector power dissipation) must be derated based on the ambient temperature Ta.
Derating must be performed based on the SOA as well. Also, please note that the input voltage (VBE for bipolar and VI(on)/VI(off) for digital) and gain (hFE and G) are affected by the ambient temperature, making it important to verify the electrical characteristics vs. temperature curves (for MOSFETs as well).