I have an entity where I'm using the following validators:

/**
 * @Assert\Callback(methods={"isValid"}, groups={"group1", "group2"})
 */
class UserProduct
{
    /**
     * @var string $title
     * @Assert\NotBlank(message="title.blank", groups={"group1", "group2"});
     */
    private $title;

    /**
     * @var Project\AuthenticationBundle\Entity\User
     * @Assert\Valid(groups={"group2"});
     */
    private $user;

Calling $this->get('validator')->validate($userProduct, array('group1')) asserts the class constraint (@Assert\Callback) and the $title property but also the $user one too, even though it's not included in the validation group. The same happens if no groups are passed to the Valid constraint.

Removing the @Assert\Valid() constraint and running the same validation again for group1 does not assert the $user property, as expected.

The MemberMetadata class appears to always force the cascading of the Valid constraint, although I'm unsure if this is exactly related to the issue I'm experiencing.

// Symfony\Component\Validator\Mapping\MemberMetadata.php
        if ($constraint instanceof Valid) {
            $this->cascaded = true;
            $this->collectionCascaded = $constraint->traverse;
        } else {
            parent::addConstraint($constraint);
        }

Running on Symfony2 master.