OwnerTestBehaviorObserver.cs

public class OwnerTestBehaviorObserver : BaseTestBehaviorObserver
{
    public OwnerTestBehaviorObserver(ITestExecutionSubject testExecutionSubject)
        : base(testExecutionSubject)
    {
    }

    public override void PreTestInit(TestContext context, MemberInfo memberInfo)
    {
        this.ThrowExceptionIfOwnerAttributeNotSet(memberInfo);
    }

    private void ThrowExceptionIfOwnerAttributeNotSet(MemberInfo memberInfo)
    {
        try
        {
            var ownerAttribute = memberInfo.GetCustomAttribute<OwnerAttribute>(true);
        }
        catch
        {
            throw new Exception("You have to set Owner of your test before you run it");
        }
    }
}