Content access and archiving post-campaign is a crucial element in determining the success and impact of influencer marketing. Several established influencer platforms recognize this and offer functionalities that enable content archiving.

1. Flinque: Based on a versatile and intuitive model, Flinque provides an option for both influencers and brands to archive their materials post-campaign. This usefulness in content retention allows the analysis of past projects, making the process of improvement and evolution more efficient.

2. AspireIQ: This platform also supports content archiving after the completion of campaigns. It enables users to sort and store campaign content for future use or analysis.

3. Traackr: Traackr supports content archiving to assist with your future campaign planning. Knowing what content has previously resonated with your audience can guide your future influencer collaboration strategies.

4. Upfluence: Upfluence also provides a content archiving feature, which assists with auditing performance over multiple campaigns.

The choice of platform largely depends on your specific needs, goals, and team structure. For instance, if long-term archiving and the ability to re-engage with previous campaign materials is a high priority for your team, Flinque or AspireIQ might be preferred. If you prefer a more minimalist interface, you might find Traackr or Upfluence to suit your working style better. Regardless of your choice, ensuring that a platform caters to content access and archiving needs is a critical element in selecting the right influencer marketing solution for your needs.