It’s no surprise that the world’s most ‘intangible’ companies, Microsoft and Apple, are easily identified. They have very real market valuations of just under $2 trillion each, much of it related to intellectual property assets like patents, trademarks and trade secrets, as well as licenses.

What is perhaps more interesting are the less familiar names on the top ten list and how they got there.

Saudi Aramco (#3, only slightly behind Apple) and Taiwan Semiconductor Manufacturing Company (#9) have only a fraction of the brand recognition of the others on the list, yet they are among the elite intangible owners. For Saudi Aramco, $1.601 trillion of its $1.644 trillion of intangible value was attributed to ‘undisclosed intangible value,’ accord to a recent report.

This raises questions about the researchers’ interpretation of intangibles for valuation. For semiconductor giant TSMC value likely is associated with their unique patents and valuable trade secrets.

TSMC employees have registered more than 140,000 individual trade secrets under a system introduced in 2013, reports the IAM blog. The company is unique in this increasingly important but difficult to value space.

“Though TSMC owns thousands of patents, it says trade secrets comprise its most important intellectual property. They are what enables the company’s lead in cutting-edge semiconductor manufacturing, which makes it one of the most important and most valuable technology companies in the world.”

For Saudi Aramco, wealth is possibly derived from industry relationships, agreements and royalties it collects, certainly not from its patent or trademark portfolio.

“The $1.9 billion that Saudi Aramco trades at is actually not at all related to intangibles,” says Efrat Kasznik, President of Foresight Valuation Group and a Stanford Lecturer. “It has everything to do with the oil market, where there are many factors impacting oil prices that directly effect this company’s stock performance, which is the driving factor in this calculation.

“You cannot compare a high-capitalized oil and gas company to say Apple by simply removing the tangible assets. It is a lot more complicated than that.”