^K1_(\w*\d*)$|^ASC_(\w*\d*)$|^GEB_(\w*\d*)$|N1_(\w*\d*)$.
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In your example K1, ASC and GEB are anchored at the beginning of the string while N1 is not. How do you determine which strings should match at the beginning of the string?

Your pattern ends with a . which will match any character except after the end of the string!