Perch · Virality Model Internal · v2 draft

The Bid-Surface Loop.

The growth engine, defined precisely enough to instrument. What spreads, what we measure, and the one product bet the whole thing rests on.

01

The loop

GC seed LOOP A · the bid blast sub sub sub · happy sub sub LOOP C · sub → sub NEW GC LOOP B · the prize → EVERY BID = AN IMPRESSION
Live / value-creating path Secondary path Loop B is the one to obsess over: it makes net-new GCs.

Three loops, not one. Loop A (GC → subs) is high volume but cold. Loop C (sub → sub) is word-of-mouth inside trade networks. Loop B, a happy sub carrying Perch to a GC who isn't on it yet, is the prize, because it manufactures net-new accounts on the valuable side.

02

The metric, defined

K = invitations per customer × conversion per invitation
K ≥ 1 means each customer more than replaces itself. Textbook viral. Be honest: in B2B with slow, considered purchases, a standalone K above 1 is rare. A solidly positive K that compounds alongside sales is already a category-defining, CAC-crushing advantage. And growth = f(K, cycle time): a modest K that turns fast beats a high K that takes a full bid season.
North star

Net-new activated accounts from existing customers' bids

One number that means "the loop is working." Everything below is a dial that moves it.

Two clocks, not one

The loop turns in weeks

Loop A resolves in the bid window (~2–4 weeks). Loop B is paced by how often a sub bids a new GC — bid frequency, not project length. So our real constraint isn't the calendar, it's conversion.

03

What to instrument

Leading indicators, because we can't wait a full bid cycle to learn whether the loop fires. Watch the flagged one hardest. It's the early signal that Loop B is real.

Bid invitations sent per GC / month The raw fuel: every invite is an impression.
Leading
Invitation → view rate Did the sub even look?
Leading
View → signup rate Cold product-led conversion.
Leading
New-sub activation rate Did they actually respond to a bid in Perch, not just create a dead account?
Leading
Subs who then used Perch with a NEW GC The leading indicator of Loop B: the one that proves virality is real.
Watch
Viral cycle time Invitation → new activated account.
Lagging
Self-serve vs. sales-sourced split Two engines, very different CAC. Never blend them into one number.
Diagnostic
04

The bet it all rests on

Make-or-break

Does a sub have to use Perch to respond to a bid, or can they reply by email and route around us? If they can route around us, the loop leaks at the worst possible point and K collapses no matter how many invitations go out. The single biggest lever on growth is how much of the bid response lives inside Perch.

05

Reputation — the conversion lever

Worst-case 1% on each loop won't grow fast enough. Verified, portable reputation is how we juice both conversion rates — and the model is Carfax: the point isn't "this sub is reputable," it's that the absence of a track record becomes the red flag. A GC can't not check.

Lifts Loop A

Claim, don't build

Pre-populate a sub's profile from activity we already see, so activating = claiming something valuable they own. And train GCs to expect a Perch record — so a sub without one looks risky.

Lifts Loop B

Flaunt the record

A sub with verified wins wants to show them off — so they bid through Perch and pull the new GC in to see the score. Reputation only pays off where it's visible.

Why it holds up

Required-to-transact makes the data true. A 10× badge means something only because those ten wins happened inside Perch — un-gameable, like Carfax's authoritative-source data. The leak-proofing bet and the reputation moat are the same bet. One caution: be fair (Carfax has been sued over errors it was slow to fix) — lean positive, keep it correctable, and expect it to compound as the network grows, not on day one.

06

Design constraints

i

Subs free in the land-grab

Subsidize the side that fuels the loop. Charge the GC: they have budget and get the value.

ii

Make sub value portable

Bid history, reusable templates, reputation they own, value that travels to every GC. That's what fires Loop B.

iii

Never spring a tax

The spreader must feel served, never surprised.

07

Pressure-test it

Rough inputs, honest defaults. Move the sliders and watch the GC-to-GC coefficient: that's whether the network feeds itself.

Loop calculator Seed: 5 GCs
150
subs invited per GC, per month
8%
cold conversion, kept low on purpose
5%
Loop B, the prize
3 mo
driven by bid frequency, not project length
×1.0
multiplies conversion + Loop-B rate · illustrative
K · GC → GC, per cycle
0.60
Amplifying
Subs seeded / GC
12
Active GCs · 12 mo
~20
Projected active GCs over 12 months
now+12 mo
Invitations counted per cycle; retained GCs keep bidding. K = invitations × conversion × Loop-B rate, with conversion and Loop-B rate scaled by the reputation lift. Directional, not a forecast. Its job is to show which lever moves growth most. Note how a ~1.3× reputation lift is enough to push K past 1.