Double End Cards
Overview π
Double end cards are an ad experience on the Chartboost Exchange that displays two sequential end cards after the main video ad β an advertiser end card followed by a Chartboost-branded end card. The user sees two skip points: the first skip advances to the advertiserβs end card, and the second skip advances to the Chartboost end card.
This format increases user engagement and campaign performance, particularly for app install campaigns.
Eligibility π
Not all video impressions qualify for double end cards. Chartboost signals eligibility in the bid request using two fields together:
- Two
companionadarrays are present in the impression object. imp.ext.cbec = 1.
Both conditions must be present for a DSP to serve a double end card. If either is absent, the impression is not eligible.
Bid Request Fields π
| Field | Type | Required | Description |
|---|---|---|---|
companionad |
Object array | Required | Two arrays present = double end card eligible. Slot 1 is the advertiser end card position; slot 2 (id="2") is the Chartboost end card position. |
companiontype |
Integer array | Optional | Supported VAST companion types: Static Resource (1) or HTML Resource (2). |
imp.ext.cbec |
Integer | Required | 1 = eligible for double end card; 0 = not eligible. |
Bid Response Fields π
| Field | Type | Required | Description |
|---|---|---|---|
bundle |
String | Required | App package name (Android, e.g. com.supercell.hayday) or numeric ID (iOS). Required for Chartboost to render the end card with correct app store assets. |
bid.ext.cbec |
Integer | Optional | 1 = allow double end card; 0 = disallow. See inference rules below. |
Chartboost End Card Control (bid.ext.cbec) π
The bid.ext.cbec field in the bid response controls whether Chartboost adds its end card. Accepted values are 0 and 1. Any other value will cause the bid to be rejected.
Inference rules when bid.ext.cbec is omitted or ambiguous π
bid.ext.cbec in response |
bundle present? |
Result |
|---|---|---|
1 or 0 (valid) |
Yes | Used as-is |
1 or 0 (valid) |
No | Overridden to 0 β Chartboost end card suppressed |
| Missing | Yes | Inferred as 1 β Chartboost end card shown |
| Missing | No | Set to 0 β Chartboost end card suppressed |
| Any other value | Any | Bid rejected |
Key rule: bundle is required to render the Chartboost end card with correct app store assets. If bundle is absent, Chartboost will always suppress the end card regardless of what cbec signals.
Publisher Exclusions π
Chartboost may exclude specific publishers from double end cards at the platform level, even when the bid request signals cbec=1. DSPs should not assume that a cbec=1 request guarantees the double end card experience will be shown to the user β publisher-level exclusions are applied server-side before the ad renders.