my $json = '{

   "required": [
        {
            "docs": [
                {
                    "sec": "11111",
                    "number": "1"
                }
            ],
            "docs": [
                {
                    "sec": "22222",
                    "number": "2"
                }
            ],
            "name": "Mary Lou"
        },
    ...
}';
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It seems strange that the value of "docs" in the quoted code should be an array with a single hash element. Was the original intention to make this an array of hashes? The posted code for printing the decoded JSON suggests this. Making this change to the JSON string produces the desired output with the posted code:

Win8 Strawberry 5.8.9.5 (32)  Mon 10/04/2021 20:14:50
C:\@Work\Perl\monks
>perl
use strict;
use warnings;

use JSON;

use Data::Dumper;

my $json = '{
   "required": [
        {
            "docs": [
                {
                    "sec": "11111",
                    "number": "1"
                },
                {
                    "sec": "22222",
                    "number": "2"
                }
            ],
            "name": "Mary Lou"
        },
        {
            "docs": [
                {
                    "sec": "33333",
                    "number": "1"
                }
            ],
            "name": "John De"
        },
        {
            "docs": [
                {
                    "sec": "4444",
                    "number": "1"
                }
            ],
            "name": "Smith Doe"
        },
        {
            "name": "Joseph D."
        }
    ]
}';

my $json_data = JSON->new;
my $data = $json_data->decode($json);

for my $dta ( @{ $data->{ required } || [] }) {
    if (scalar @{ $dta->{ docs } || [] } ) {
        for my $doc_data (@{ $dta->{ docs } || [] }) {
            if ($doc_data->{'sec'}) {
                print "\n Yes: $dta->{'name'} - $doc_data->{'sec'} ",
                      "| $doc_data->{'number'} \n";
                }
            }
        }
    else {
        warn "\n No sec value, just the name: $dta->{'name'} \n\n";
        }
    }
^Z

 Yes: Mary Lou - 11111 | 1

 Yes: Mary Lou - 22222 | 2

 Yes: John De - 33333 | 1

 Yes: Smith Doe - 4444 | 1

 No sec value, just the name: Joseph D.
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