Viewability confirmation

MRC

Yandex DSP verifies viewability based on MRC (Media Rating Council) standards. The MRC metric measures whether an ad was physically available for a human user to see, rather than just rendering on the page.

For an SSP, this is a critical indicator of inventory quality:

50% rule for 1–2 seconds

An ad counts as viewable when two conditions are met:

• Area: At least 50% of the ad's pixels are within the viewable area of the screen (viewport).
• Duration: The ad remains in this area continuously for at least 1 second for banners or 2 seconds for video.

How this works for a SSP

When an auction happens, the SSP shares viewability data with buyers (DSPs). This can be done in two ways:

• Historical viewability: The SSP passes along the average viewability rate for that specific ad unit based on past data.
• Real-time measurement: The SSP uses JS metrics like VPAID or OMID to catch the exact moment the 50/1 conditions are met and sends out a confirmation signal.

Why it matters

• Pricing: Advertisers are willing to pay more for high-visibility inventory (typically above 80%).
• vCPM: Shifting from paying for standard impressions (CPM) to only paying for viewable impressions (vCPM).
• Low viewability often points to hidden frames (pixel stuffing) or bot-driven traffic.

Today, SSPs rely on the OMID (Open Measurement SDK) to standardize viewability tracking across all channels, even inside mobile apps.

OMID (Open Measurement SDK)

OMID (Open Measurement Interface Definition) is an open standard and API developed by the IAB Tech Lab. It helps third-party vendors (such as IAS, DoubleVerify, and Moat) track ad viewability and fraud across web and mobile app environments via a unified kit known as the OM SDK. See the OMID documentation.

Key features and capabilities

• Standardization: Developers integrate a single OM SDK that collects viewability signals and sends them to whichever verification partner the advertiser chooses.
• Transparency: OMID acts as a digital intermediary, gathering data on when, where, and how long an ad was on screen, and sending it to the measurement vendor's JavaScript tag.
• VPAID successor: OMID replaces the older VPAID standard in video and mobile apps, eliminating common bugs and performance delays.
• Format support: This standard handles native banners, interstitials, and video ads across both HTML5 and native players.

How it works

• Integration: The publisher embeds the OM SDK directly into their app or uses an ad SDK (like the Google Mobile Ads SDK) that already includes it.
• Session start: When an ad unit serves the ad, the SDK creates an OMID session and starts monitoring its on-screen presence.
• Signal transmission: If the ad creative contains a verifier tag, OMID passes real-time data about pixel viewability percentages and video events (like start, pause, and complete) to that verifier.
• Handling obstructions: The API allows developers to mark specific UI elements (such as close buttons or player controls) as "friendly obstructions" so they don't negatively impact the viewability score.

For Yandex DSP, having OMID signals is a core requirement when buying inventory. Traffic without such support is often excluded from bidding or valued much lower because it can't be verified using independent methods.