In my current project I had to clean up the existing process chains. A lot of process chains were created via SPOs and not really used in the system. First I had to check, if one is used in a another process chain or in which one they are used.
In the transaction SE16 open table RSPCCHAIN and insert into VARIANTE the technical name of your process chain.
The column CHAIN_ID shows you the corresponding meta-chain.
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