Online PHP editor | output for bVqEN6

<?php $stocks = collect( [ ['sku' => '123', 'batch' => '123', 'manufacturing_date' => 2021, 'qty_total' => 1], ['sku' => '123', 'batch' => '123', 'manufacturing_date' => 2021, 'qty_total' => 2], ['sku' => '123', 'batch' => '123', 'manufacturing_date' => 2020, 'qty_total' => 3], ['sku' => '5', 'batch' => '123', 'manufacturing_date' => 2020, 'qty_total' => 4], ] ); return $stocks->groupBy(['sku','batch' , 'manufacturing_date'], true)->map(function($items){ $firstItem = $items->values()->first()->values()->first(); return collect($firstItem->first())->merge([ 'qty_total' => $firstItem->sum('qty_total') ]); })->values();