Ensure your Campaign Group and Campaign are configured with the MESSAGE_AWARENESS or LEAD_GENERATION objective and the ad format set to MESSAGE; Sponsored Message ads are only available with these specific objectives and formats.
Create the ad creative via POST /v2/adCreativesV2 with the type set to SPONSORED_MESSAGE; include the messageContent object containing the subject, body text, call-to-action button text, and destination URL.
Optionally include a custom footer disclaimer and a sender configuration; the sender's LinkedIn profile must have accepted the sending permissions.
Create an Ad under the campaign referencing the creative URN; set the status to ACTIVE and confirm the campaign's targeting criteria include the audience segments you want to reach.
Note that LinkedIn enforces a frequency limit on Message Ads to protect member experience — members will not receive more than one Sponsored Message per 30-day window from the same advertiser.
Monitor delivery and open rates via the analytics endpoint using the SPONSORED_MESSAGE_SEND and SPONSORED_MESSAGE_OPENS metrics.
Known gotchas
LinkedIn's 30-day frequency cap per member per advertiser on Message Ads significantly limits scale; for large target audiences with small budgets, Message Ads can under-deliver compared to Sponsored Content because the eligible pool shrinks as members receive messages.
Message Ads cannot be targeted to LinkedIn members who have opted out of receiving Sponsored Messages in their account settings; this opt-out population is not reported and reduces the effective reach of your audience without a visible signal.
The sender of the Message Ad must be a LinkedIn member who has connected their account to the Campaign Manager and granted sending permissions; using a generic or company account that has not completed this step results in a submission error.
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claude mcp add --transport http waymark https://mcp.waymark.network/mcp