@foreach($contacts as $contact)
    <tr>
        <td><input type="checkbox" class="contact-checkbox" value="{{ $contact->id }}"></td>
        <td>{{ $contact->last_name }}</td>
        <td>{{ $contact->email_address }}</td>
        <td class="contact-groups" data-groups="{{ $contact->groups->pluck('id')->join(',') }}">
            @foreach($contact->groups as $group)
                <span class="badge badge-info">{{ $group->name }}</span>
            @endforeach
        </td>
    </tr>
@endforeach