Thanks! I changed the line to this:

if ( $line =~ /\d{4,}/ { $date = $1; }
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But the part that I think is causing the error is this one:

else { $seqs{$sequence} = "$date;$orig;$desg;$body"; }
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Here is what the error looks like:

[bluethundr@cc126-200:~/perl] $:./3par-test5.pl 
Use of uninitialized value in pattern match (m//) at ./3par-test5.pl l
+ine 29, <MYFILE> line 1.
Use of uninitialized value in concatenation (.) or string at ./3par-te
+st5.pl line 30, <MYFILE> line 1.
Use of uninitialized value in concatenation (.) or string at ./3par-te
+st5.pl line 30, <MYFILE> line 1.
Use of uninitialized value in concatenation (.) or string at ./3par-te
+st5.pl line 30, <MYFILE> line 1.
Use of uninitialized value in concatenation (.) or string at ./3par-te
+st5.pl line 30, <MYFILE> line 1.
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For greater context, here is the loop in which this statement sits:

while (<MYFILE>) {
    next if (m/^$/);
    last if (m/^Press.*/);
    my ( $line, %seqs, $sequence, $date, $orig, $desg, $body );
    if ( $line =~  /\d\d:\d\d:\d\d/g { $date = $1; }
    else { $seqs{$sequence} = "$date;$orig;$desg;$body"; }
}
[download]

Thanks again!