B2B Influencer Marketing: How Harmonie Mutuelle Drives Qualified Traffic with Vincent Hagenbourger

In social protection and workplace health, capturing the attention of HR decision-makers and business leaders takes far more than a simple advertising presence. To build lasting trust, B2B brands need to partner with credible voices and set up long-term editorial programmes: that is the whole point of B2B influencer marketing.

This B2B influencer marketing case study shows exactly that ambition: the campaign run by Harmonie Mutuelle with B2B expert Vincent Hagenbourger, orchestrated by the agency Les Années Folles. The idea: a co-written newsletter, published on the brand’s blog and then amplified on LinkedIn, which generated over 107,000 impressions.

Contents

• The challenge: going beyond the sponsored post with co-created content
• The “flywheel” mechanism: co-written newsletter, blog and LinkedIn amplification
• The role of B2B influencer marketing agency Les Années Folles: from editorial committee to governance
• B2B influencer campaign results: over 107,000 impressions and peak engagement
• Key takeaways for your B2B influence strategy

The challenge: going beyond the sponsored post with co-created content

Most B2B brands make the mistake of treating B2B influence as a series of one-off operations. For Harmonie Mutuelle, the goal was quite different: to build over time and develop strong topical authority on HR, prevention and occupational health issues.

By choosing co-authoring, Harmonie Mutuelle did not simply ask a B2B influencer to relay a sales message. The brand brought Vincent Hagenbourger’s expertise right into the heart of its editorial production.

This approach combines the institutional legitimacy of the mutual insurer with the authentic tone and closeness of a LinkedIn content creator recognised by peers.

The “flywheel” mechanism: co-written newsletter, blog and LinkedIn amplification

Instead of keeping channels apart, the strategy relies on a flywheel in which each step feeds the next:

• Co-writing the newsletter: Harmonie Mutuelle and Vincent Hagenbourger co-write a thematic newsletter for professionals.
• Hosting on the blog (owned media): the article based on the newsletter is published directly on Harmonie Mutuelle’s blog. This keeps the content on the brand’s owned media and strengthens its SEO.
• LinkedIn amplification (drive-to-blog): Vincent Hagenbourger then publishes a LinkedIn post to break down the topic and send their community to Harmonie Mutuelle’s blog.
• Taking part in the quarterly editorial committee: Vincent joins the editorial committees directly to define the key topics and keep Harmonie Mutuelle’s priorities aligned with what the creator’s audience cares about.

This virtuous loop ensures that every drop of attention generated on social media turns into qualified traffic on the brand’s website.

The role of B2B influencer marketing agency Les Années Folles: from editorial committee to governance

Behind the smooth running of this campaign lies rigorous framing work by the Les Années Folles team.

• Talent selection and support: tailored matchmaking to make sure Vincent Hagenbourger’s tone stays natural while meeting the brand’s strategic requirements.
• Governance and wave tracking: orchestrating the monthly publishing calendar (from the Flash PLFSS newsletter, on France’s social security financing bill, to the regular editions from January to July) to keep a regular appointment with decision-makers.

“Responsive support and a real understanding of our challenges. The B2B influencer selected by Les Années Folles supported us perfectly throughout the collaboration.”
Annelore Chrismann, Harmonie Mutuelle

B2B influencer campaign results: over 107,000 impressions and peak engagement

Thanks to this regularity and the quality of the co-created content, the campaign’s performance shows the impact of the programme:

• Over 107,000 cumulative impressions on Vincent Hagenbourger’s posts.
• Engagement rate (ER) peaks of 3.25% and 3.0% (on the June and January editions), well above B2B market averages.
• Over 600 cumulative saves (including 146 saves on a single post in March), proof that decision-makers keep these articles as practical reference guides.

Key takeaways for your B2B influence strategy

The Harmonie Mutuelle x Vincent Hagenbourger campaign proves that B2B influence on LinkedIn should not be treated as an isolated island. By connecting co-created expertise, owned media and social amplification, you build a lasting marketing asset.

To discover more strategies and case studies broken down, such as our earlier B2B influencer campaign for Harmonie Mutuelle, visit our B2B influence blog.

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