200,000 Claimants Walked Into a Mass Arb. Nobody Modeled What Happens Next.

A court filing in the Meta social media settlement matter recently disclosed that counsel for more than 200,000 individual claimants had sent mass arbitration demands over alleged Instagram-related harms. Two hundred thousand. That number got a lot of attention in plaintiff-side circles, and for good reason. It is an extraordinary volume of individual demands, possibly the largest coordinated mass arbitration effort on record.

But here is the number nobody is talking about: what does it cost to complete 200,000 claimants?

Not sign them. Not file them. Complete them. Get them through every document, every verification step, every release, every payment authorization, across whatever timeline the settlement or arbitration framework dictates. That is where the real P&L lives, and at this scale, the math changes in ways most firms have never had to confront.

Volume Is Not the Hard Part Anymore

Five years ago, signing 200,000 claimants was the headline challenge. Today, between Meta ad spend, legal lead aggregators, and SMS-based intake, the front end of a mass arb campaign is a solved problem for well-capitalized firms. The cost per lead on a consumer privacy matter can run $80 to $250 depending on channel and targeting. Even at the high end, a firm with enough budget and a clear claim can fill a roster.

The hard part is what happens after the roster is full.

Every one of those 200,000 claimants needs to receive outreach. Respond. Verify their identity. Sign documents. Possibly re-sign if terms change. Possibly provide additional information months after their initial engagement. And they need to do all of this within a window that may be 90 days, 180 days, or longer, depending on the procedural framework.

At 10,000 claimants, you can muscle through that with a decent paralegal team and a basic outreach cadence. At 200,000, you cannot.

The Completion Cost Curve Bends at Scale

Here is what most firms miss when they model completion on a large matter: the cost per completed claimant does not stay flat as volume increases. It bends upward.

Why? Three reasons.

1. Channel saturation. When you are reaching out to 200,000 people over SMS, email, and phone, your deliverability degrades. Carrier filtering gets more aggressive. Email domains accumulate spam complaints. Caller ID reputation drops. Each additional outreach touch costs more in infrastructure management than the one before it.
2. Response decay across cohorts. Not all 200,000 claimants signed up at the same time or with the same level of intent. The first 50,000 may have been highly motivated. The last 50,000 may have clicked a Facebook ad at 11 p.m. and barely remember doing it. Those late-funnel claimants require more touches, more re-engagement, more hand-holding. The marginal cost of reaching them is higher.
3. Document and verification complexity. At scale, every percentage point of document error, failed ID verification, or unsigned release multiplies into thousands of individual follow-up tasks. If 5% of your claimants have a document issue at 10,000 scale, that is 500 tasks. At 200,000 scale, that is 10,000 tasks. Each one requires a touchpoint. Each touchpoint costs money and time.

The firms that model completion cost as a flat per-claimant number are building their budgets on a fiction. The real cost curve looks more like a yield curve: cheap and efficient at the front, increasingly expensive as you chase the last 10 to 15 percent you need to hit threshold.

What 200,000 Claimants Actually Requires

Let me put some rough numbers on this, because the math is instructive even if your matters are a tenth of this size.

Assume a legacy claims administrator charges $20 per claimant. On 200,000 claimants, that is $4 million in admin fees alone. Now assume the administrator's outreach model is the standard one: send a notice, send a reminder, maybe a second reminder, wait. That model typically yields completion rates in the 60 to 70 percent range. On a matter with an 85% release threshold, you are short by 15 to 25 points. You need additional outreach waves, escalation to phone, possibly AI-assisted follow-up, possibly physical mail for unreachable claimants.

Each of those escalation layers adds cost. And on a legacy admin's rented tech stack (where they are licensing e-signature from one vendor, SMS from another, email from a third, and caller ID from a fourth), every additional touch runs through someone else's margin. The admin is not incentivized to send touch number twelve. They already collected their per-claimant fee on touch number one.

This is the structural problem with legacy administration at mass arb scale. The business model was designed for class action notice, where you send a mailing and let inertia do the rest. Mass arb completion is the opposite of inertia. It requires persistence. Persistence requires infrastructure you own, not infrastructure you rent.

The Infrastructure Question Nobody Asks Before Filing

If I were advising a firm that was about to file 200,000 mass arb demands (or 20,000, or 2,000), the first question I would ask is not "what's your CPA?" It would be: "What does your outreach stack look like at month six?"

Because month one is easy. Everyone opens the first text. Most people read the first email. Some answer the first call. But by month six, you are reaching the claimants who ignored the first five touches. You are re-engaging people whose phone numbers changed. You are chasing signatures from people who started the process and dropped off. And you are doing all of this while maintaining deliverability, compliance, and a consent chain that holds up under scrutiny.

The firms that hit threshold consistently are the ones who built for month six before they filed a single demand. They own their document signing, so they control the experience. They own their SMS and email delivery, so they control deliverability and can iterate on cadence without asking a vendor for permission. They use AI to handle routine claimant inquiries (over 80% of them, in our experience), which frees human operators to focus on the hard cases. And they align their admin's billing to the outcome: the firm pays when the threshold is hit, not when the notice is sent.

That is what threshold-aligned billing actually means. It is not a pricing gimmick. It is an incentive structure. When your admin only gets paid if you hit your release threshold, every touchpoint the admin sends is in service of the same goal you have. When your admin gets paid per claimant on day one, their incentive is to sign up claimants and send a notice. Your incentive is completion. Those are not the same thing.

The Real Lesson of 200,000 Demands

The Meta matter is exceptional in scale, but the lesson it teaches is universal. Every mass arb campaign, regardless of size, is a completion problem. The firms that win are the ones who model the back end before they fund the front end.

Before you spend $500,000 on claimant acquisition, ask: what is my per-claimant completion cost at 70%? At 85%? At 93%? How does that cost change if my outreach cadence needs to extend from 90 days to 180 days? What happens to my margin if I need to add phone outreach at month four because SMS deliverability degraded?

If you cannot answer those questions, you are not running a mass arb campaign. You are running a lead-gen campaign and hoping someone else figures out the rest.

Hope is not a completion strategy.