Myth: add more header-bidding partners to raise RPM

Myth: add more header-bidding partners to raise RPM

The "stack more demand" advice has a hard ceiling most people blow past.

What it does — each bidder competes in the client-side auction to lift your clearing price.
Setup effort — 4/5 per partner.
The correction — every extra client-side bidder adds latency and JS weight, and most resell the same DSP demand you already have. Past ~6-8 partners you add timeout risk and bid loss far faster than incremental price competition. The winning move is pruning duplicate demand, not piling it on.
RPM lift seen — cutting from 11 to 7 deduped partners raised RPM 5% via fewer timeouts.
Pros of pruning — faster auctions, better Core Web Vitals.
Cons — political with ad networks who want in.

Lift: ★★★★☆ — Risk: ★★★☆☆
Best for: bloated wrappers. Skip if you run server-side — different math entirely.