Now HERE is the difference between what we commonly call "Synthetic" and "True Synthetic". It all has to do with what they start with to make the product and what the API (American Petroleum Institute) allows to be called "Synthetic".
Some synthetic oils are made from TYPE III base stocks. Type III is conventional oil. To make it into a synthetic it's synthesized in the presence of hydrogen under very high pressure to produce a lubricant (while mineral based) that has more uniform molecules and better lubricating properties than standard conventional oil. The API allows this to be marketed as "Synthetic" oil in the United States. In many countries such as Germany and Japan, a lubricant that starts with a Type III base CANNOT be marketed as a Synthetic.

A second method is commonly used whereby the base product is a Type IV lubricant (polyolefin) which while still an organic compound is not a petroleum product (oil). The API commonly classify organic compounds that are not petroleum based as PAOs. Because polyolefin is organic and not man made, lubricants produced from it are not "100% synthetic" but because it's not petroleum it can be marketed as a Synthetic Lubricant in those countries who DO NOT allow oils that begin as conventional petroleum to be marketed as such.

The third is a TRUE or 100% SYNTHETIC Lubricant, whereas the base material is not petroleum or organic (PAO) and instead is a 100% man made product. These bases are generally diesters, polyolesters or benzenes.

I'm not going to get brand specific here, but MANY oils marketed IN THE UNITED STATES as "Synthetic" not only start with a petroleum (conventional oil) base but in many cases contains up to 69% plain old conventional oil. As long as there is 31% synthetic oil (which can also be made from conventional oil) then it can be called "Synthetic".