Numerous brands suspended ad spending on YouTube after they discovered some of their ads were appearing alongside videos featuring objectionable content. Video analytics firm OpenSlate is now offering an auditing service to address the issue. Ad companies such as Horizon Media, Magna Global, Omnicom Media Group and Publicis Media are using the service, hoping “to reassure marketers that their ads on YouTube are appearing alongside content that’s safe for their brands,” reports The Wall Street Journal. OpenSlate also provides “a deep analysis to ensure clients are getting what they pay for when they buy ads on YouTube, such as reaching the right target audience.”

YouTube has also taken steps to address the issue, including an improvement to the tech used for screening videos “and allowing third-party measurement companies to monitor where ads appear on the site.”

Agencies and brands are now turning to “independent measurement firms that can help them get a more comprehensive analysis of where their ads are running,” notes WSJ, “including a full list of videos against which their ads appeared and details about the content of the videos.” It is an arduous task, since YouTube currently features more than 350 million ad-supported videos.

“As part of our commitment to provide even more transparency and visibility to our advertising partners, we’ve been working with trusted vendors to provide third party brand safety reporting on YouTube,” said a spokeswoman for Google. “We are working with companies that are MRC-accredited for ad verification on this initiative and will begin integrating these technologies shortly.”