How Spark Ads work
A creator posts a video on their own account. They generate a Spark Ads authorization code for that post and send it to the brand. The brand enters the code in TikTok Ads Manager, and the post becomes an ad that runs from the brand's account while still showing the creator's handle, likes, and comments. The creator sets how long the authorization lasts; check TikTok's current docs for the exact steps and the available durations, since the interface changes.
The alternative is a non-Spark ad, where you upload the video file and it runs under your brand's ad account with your handle. Same video, different presentation. Spark keeps the social proof attached to the post; upload starts from zero.
What to write into the agreement
Name the authorization explicitly: which post, for how long, and whether the creator must keep the post live for the whole period. A sample contract line: "Creator will post Video 1 to their TikTok account and provide a Spark Ads authorization code valid for 60 days; Creator will not delete the post during that window." Price it as paid usage, because that's what it is.
Also agree what the brand can change. Spark Ads let the advertiser add a call-to-action and choose targeting, but the video and caption belong to the creator's post. If you need caption edits or a different cut, that's a file delivery, not Spark.
How it's used
Contract clause: "Creator grants TikTok Spark Ads authorization on the delivered post for 60 days at no additional fee beyond the stated usage rate."
Media buyer to creator: "The organic post is at 40k views, can you send the Spark Ads code so we can put budget behind it this week?"