Magnite is the largest independent sell-side advertising company, providing technology for publishers to maximize ad revenue across CTV, streaming, and digital formats.

Sovrn is a publisher technology platform offering data and monetization tools, including ad exchange, commerce/affiliate solutions, and data monetization for the open web.

Sharethrough is an omnichannel supply side platform offering human-centric programmatic advertising solutions with enhanced ad experiences for brands and publishers.

Snigel is an ad technology, native video, and header bidding company helping publishers grow ad revenue through yield management and optimization.

SmartyAds is a full-stack programmatic ad tech company offering DSP, SSP, and Curated Deals solutions for profitable ad monetization and media buying.

Adpushup is an ad revenue optimization platform helping web publishers maximize yield through header bidding, ad layout optimization, and adblock recovery.

Headerbidding.co appears to be an uninitialized domain, likely intended for a service related to header bidding technology in digital advertising.