A simple Google-search ("magento product attribute via customer group") reveals that this question has been asked before on stackoverflow.
"Displaying custom product attributes based on customer group (Magento)"
Summarized:
In the view (probably app/design/frontend/default//template/catalog/product/view.phtml
) you want to have this logic, use the following code:
$_isLoggedIn = $this->helper('customer')->isLoggedIn();
if ($_isLoggedIn == true){
$_groupId = Mage::getSingleton('customer/session')->getCustomerGroupId();
if ($_groupId === 'X') {
// output your product attribute
}
}
X
being the customer group the attribute should be shown for. Because having scattered random ID's like these in view files is (in my personal opinion) a bad practice, you probably want to abstract that away a bit so you can easily modify the product attributes related to a specific customer group.