From Claud AI

On Apple Silicon Macs private keys used for codesigning are generated inside the Secure Enclave — a dedicated security chip that is physically unique to each Mac.

The Secure Enclave has its own unique SEID (Secure Enclave ID) that is hardwired into the hardware.
When a private key is created it is cryptographically bound to the specific Secure Enclave that created it.
The key literally cannot exist or function outside that specific piece of hardware.
This is by design — it is what makes the key secure.

Running system_profiler SPSecureElementDataType reveals a potential discrepancy between the hardware SEID and System OS SEID:

SEID:           04472C8BB9209002413205682832707603DBF0E05E8753C1
System OS SEID: 04472C8BB92090024132056828327076FFDBF0E05E8753C1
These values differ at bytes 17-18 — 03DB vs FFDB.


I think this slight difference implies a temporary h/w error when copying to the OS.