Online advertisers had a problem they could not see: many of their ads loaded below the fold, beside ugly content, or in front of bots. Integral Ad Science sold them the evidence. Its software checked each ad for viewability, brand safety, and fraud, and reported back. When IAS went public in June 2021, ad spending was surging after the pandemic slump, and big brands wanted proof their money reached actual human eyes.

An Auditor for Ads

IAS was founded in New York in 2009, as brands moved more of their budgets to automated ad buying. In that system, a brand might never know which site showed its ad. The bet was that advertisers would pay an independent referee to check every placement. IAS grew into one of the main ad verification firms, with DoubleVerify as its chief rival. The private equity firm Vista Equity Partners took control in 2018.

From Vista to Novacap

IAS priced at $18 a share and began trading on the Nasdaq as IAS on June 30, 2021. The stock closed its first day up about 14 percent, valuing the company near $3.3 billion. Its shares later slid as growth slowed. In December 2025 the Canadian private equity firm Novacap took IAS private for $10.30 a share in cash, valuing it at about $1.9 billion.

Cover: Old Man with a Book, Old Man with a Magnifying Glass, Old Man Holding a Medallion, Giovanni Domenico Tiepolo. Art Institute of Chicago, public domain. Chosen for an old man with a magnifying glass (verification).