PubMatic might be a bit more popular than Adform. We know about 1 link to it since March 2021 and only 1 link to Adform. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
I would highly recommend starting from Adform or Smart. Those are quite easy to manage if you just started your journey with programmatic. Adform: https://site.adform.com/ Smart: https://smartadserver.com/demand-partners/. Source: over 2 years ago
This lead me to a CIDR owned by PubMatic Inc (pubmatic.com is blocked by the Adaway list):. Source: almost 2 years ago
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