Close, but that still matches PH-000 due to the .{0,4} clause. I think that 
/^PH(?:.{0,3}|.*(?![HI]-000).{5})$/

[download]
does it. 
-sauoq
"My two cents aren't worth a dime.";

In reply to Re: Re: old Perl regex problem by sauoq
in thread old Perl regex problem by GhodMode

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