COLD SPRING HARBOR, NY -- ZDT topped Nippon Mektron (Mektec) as the world's largest printed circuit fabricator in 2017.

It marks the first time ZDT, the offshoot of Hon Hai, topped the rankings.

The data were compiled by Prismark Partners, an industry research firm.

Zhen Ding Technology (ZDT) reported revenue of $3.59 billion, followed by Mektec at $3.32 billion. Both firms are primarily flex circuit providers, and the sales include component and assembly revenue. Component and back-end revenue could make up as much as half the firm's overall sales.

In third was TTM Technologies, the highest ranked US company on the list, followed by (in order) Unimicron, Compeq, and Tripod.

Almost all the top 10 on the Prismark are major suppliers to Apple.