<?php
 
$data = [
	['name' => 'company1', 'value' => 123],
	['name' => 'company1', 'value' => 65456],
	['name' => 'company1', 'value' => 435],
	['name' => 'company1', 'value' => 234235],
	['name' => 'company2', 'value' => 65464],
	['name' => 'company2', 'value' => 53543]
];
 
$arr_sum = [];
 
foreach ($data as $companies) {
    $company = $companies['name'];
    $value = $companies['value'];
 
   if (!isset($arr_sum[$company])) {
       $arr_sum[$company] = 0;
   }
 
   $arr_sum[$company] += $value;
} 
 
var_dump($arr_sum['company1']); //int(300249)
var_dump($arr_sum['company2']); //int(119007)

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