DoubleVerify went public at $27 a share. Five years later Nielsen agreed to buy it for $13.60. In between, it checked more than 5 billion digital ad transactions a day. Brands paid it to check each ad. It told them whether a person or a bot saw it, whether it ran in the right country, and whether it sat next to hate speech. When DoubleVerify filed in March 2021, ad budgets were pouring online, and so was fraud.

An Auditor for Every Ad

DoubleVerify started in New York in 2008. Online ads ran across thousands of sites, apps, and exchanges, and advertisers had no neutral way to see where their money went. DoubleVerify sat in the middle as an independent referee. Its software could block a bad placement before the ad was bought and measure the ones that ran. It boiled the results into one score, the DV Authentic Ad. Providence Equity Partners bought a controlling stake in 2017.

From Twenty-Seven to Thirteen Sixty

DoubleVerify priced its IPO at $27 a share on April 20, 2021, and listed on the NYSE as DV the next day. Tiger Global bought $60 million of stock alongside the deal. Growth slowed, and the stock slid. In August 2026 the parent of Nielsen agreed to buy DoubleVerify for $13.60 a share in cash, about half its IPO price. The deal was still pending in October 2026.

Cover: Reflection, Mary Cassatt. Art Institute of Chicago, public domain. Chosen for a reflection (seeing double, checking twice).