To me they’d need to add some kinda modifier like the word with to give them that lingual wiggle room. “These oils are 100% fully synthetic with Group 4 and Group 5 lubricants” It’s synthetic with A and B, we’re just not telling you it’s mostly C.It’s just marketing BS. It leaves plenty of wiggle room because they are “100% synthetic” and contain some Group 4 or 5.