Full-path attribution (W-shaped plus the close)
Full-path attribution is the W-shaped model extended to four milestones: first touch, lead creation, opportunity creation, and the final closing interaction. Each milestone takes a fixed large share and the remaining credit is distributed across other touches. It is designed for long B2B sales cycles where the deal-closing interaction is a distinct, measurable event worth its own credit.
What this means
Full-path attribution recognizes four pivotal interactions in a journey: the first touch, the touch that creates the lead, the touch that creates the opportunity, and the touch present at the close. A common convention assigns a large fixed share (for example ~22.5% each, with a small remainder spread across other touches), though tools vary.
It is the longest of the milestone-based rules family — U-shaped credits two milestones, W-shaped credits three, and full-path credits four.
Where it fits
Full-path is built for enterprise B2B, where months pass between discovery and signature and where the closing interaction (a final demo, a contract page) is a real, datable event. Crediting the close acknowledges late-stage marketing and sales-enablement content that pure lead-focused models ignore.
Like its siblings, the weights are conventions, not measured contributions, and the model is only as good as the milestone timestamps it depends on. When even four milestones cannot capture a journey, teams move toward algorithmic models such as Shapley or Markov attribution.
- Milestones: first touch, lead, opportunity, close
- Each milestone takes a large fixed share
- Remaining touches split a small remainder
How it appears in analytics and logs
Four credit peaks along a path indicate full-path attribution keyed to first, lead, opportunity, and close; touches outside those milestones will always look small here.
Diagnostic use case
Use full-path attribution when your sales cycle has a distinct closing event after opportunity creation and you want that closing touch to receive explicit credit.
What WebmasterID can help detect
WebmasterID records first-party touchpoints you can align to milestone timestamps, so you can see which interactions coincided with each stage of a long cycle in your own data.
Common mistakes
- Using full-path when there is no distinct, datable closing event.
- Treating the fixed weights as causal measurement.
- Relying on unreliable opportunity or close timestamps.
Privacy and accuracy notes
Full-path attribution keys credit to recorded milestone events, not to identity. Its accuracy depends on correctly stamping which touch produced each milestone, including the close.
Related pages
- W-shaped attribution (three key milestones)
W-shaped attribution extends the U-shaped idea by recognizing three milestone interactions rather than two: the first touch, the lead-creation touch, and the opportunity-creation (or closing) touch. Each milestone receives a large fixed share — commonly 30% apiece — and the remaining credit is spread across other touches. It is popular in B2B funnels with defined lifecycle stages.
- Shapley value attribution
Shapley value attribution applies a concept from cooperative game theory: it treats channels as players in a coalition and assigns each one credit equal to its average marginal contribution across all possible orderings of channels. The result is a principled, order-independent way to split conversion credit. It underpins data-driven attribution in several analytics products.
- U-shaped attribution (position-based 40/20/40)
U-shaped attribution is the position-based model in its classic form: the first interaction and the conversion-driving interaction each receive a large fixed share (commonly 40% each), and the remaining credit is split among the middle touches. It is a rules-based heuristic that values discovery and closing equally, and it is the lens many tools mean when they say 'position-based'.
- Attribution analytics
Align first-party touchpoints to long-cycle milestones.
Sources and verification notes
- Google Analytics Help — Attribution model overviewDocuments the rules-based model family; full-path's four-milestone form is an established B2B convention rather than a single official spec.
Last reviewed 2026-06-24. Facts are checked against primary/official sources where available; uncertain specifics are marked “Data not yet verified” rather than guessed.