Most ad platforms default to last-click attribution: whoever touched the conversion last gets 100% credit. That flatters brand search and starves prospecting. Multi-touch attribution (MTA) distributes credit across the path — but only if you can see the path.

A realistic B2B / FinServ journey

−12d  organic/search   /blog/ecsp-guide
−9d   paid/meta          prospecting reel
−3d   paid/google        brand search
−1d   direct             /signup
 now  conversion         lead logged

Last-click says “direct.” Multi-touch says Meta and organic assisted; Google captured intent; direct closed. Budget decisions change when you see the chain.

Common MTA models (and trade-offs)

  • Linear — equal credit to each touch. Simple, often too flat.
  • Time decay — more credit to recent touches. Good for short cycles.
  • Position-based (U-shaped) — 40% first, 40% last, 20% middle. Popular for considered purchases.
  • Data-driven — platform ML (Google DDA, Meta). Better than last-click, still platform-biased.

Operator teams pick a model that matches sales cycle length, then reconcile with first-party logs — not the other way around.

Assisted conversions you should track

Report assisted rate by channel: “% of conversions where this channel appeared earlier in the path.” High assist + low last-click on Meta prospecting often means do not cut prospecting when brand search ROAS looks perfect.

Identity is the hard part

Cross-device and cross-domain identity requires a stable first-party ID, click ID capture on landing, and consent where GDPR applies. Without that, MTA collapses to guesswork.

We log the nexus on our stack — every touchpoint, every click ID — then decide budget moves. Platform dashboards alone are not enough.

Next: First-Party Attribution Without a SaaS Vendor.