There is no way that is correct as any sort of generally true statement. A random google shows that it's highly sector dependent, but it's probably closer to 2

There is no way that is correct as any sort of generally true statement. A random google shows that it's highly sector dependent, but it's probably closer to 20%. Having worked in consumer electronics, and knowing rough BOM cost of products that we made in the millions, I can say (at least for the companies I worked for), that there wasn't anywhere close to a 300% multiplier, even going from BOM cost to MSRP. Even extreme outliers like Apple (who supposedly have a raw BOM cost of $475 on an MSRP of $1099 for the 14 Pro Max) don't get to 300%. That markup goes directly to Apple; As a retailer, you might be making 10%.