The 1N6272A-E3/54: That peak rating tells you what single-event transient the diode absorbs before the die overheats — the 96.2 A peak pulse current is the other half of the absorption ceiling, and both numbers must stay within the datasheet SOA for the application to survive repeat events.
Clamping voltage — what the downstream circuit actually sees
The reverse standoff (typ) is 9.4V — below this the device sits off and adds negligible leakage to the rail. The minimum breakdown is 10.5V, so the clamping window runs from 10.5 to 15.6V across the rated current range. For a 12V rail, 9.4V standoff gives comfortable headroom in normal operation; when a surge exceeds that threshold the clamp locks the downstream bus at or below 15.6V, protecting whatever is behind it.