Klaviyo helped design the protocol that could let AI agents bypass its emails; insiders sold $200 million
Sierra and Meta's draft Personal Agent Protocol would let consumers' AI agents buy, return and rebook directly with brands, past the marketing messages Klaviyo sells. Klaviyo joined the design table as insiders net-sold $199.9 million of its stock over 12 months.
Vincent Jiang · 3 min read
Ed Hallen co-founded Klaviyo−1.96% — Klaviyo, down 1.96 percent today and still serves as a director and ten-percent owner, per the filing. On October 7 he sold 97,482 shares at a weighted average of $17.40, about $1.7 million, and gifted 17,885 more to a donor-advised fund the next day 1.
The Form 4, the SEC filing that discloses insider trades, landed on October 9, in the same week Sierra~$10B — Sierra, private, latest valuation ~$10B, the agent company co-founded by Bret Taylor, published a draft of the Personal Agent Protocol naming Klaviyo among 35 design partners, beside PayPal+0.65% — PayPal, up 0.65 percent today, Visa and messaging rival OneSignal 23. The sale ran under a Rule 10b5-1 plan, a trading schedule set months in advance and adopted on June 1 1, so its timing is not a reaction to the draft.
One agent session instead of the inbox
Sierra announced the draft, called Poppy, on October 6 with eight launch partners: Meta+3.84% — Meta, up 3.84 percent today, Genesys, Instinct, NiCE, Rocket, Shopify+3.41% — Shopify, up 3.41 percent today, Stripe and Walmart 2. Poppy would let a consumer's personal agent identify itself, carry the customer's permission and finish a return, a rebooking or a purchase through a brand's website, APIs or its own agent 2.
The draft's stated goal is that a brand "sees the whole journey instead of disconnected fragments" 2. Klaviyo, with more than 205,000 paying customers by its own count, sells those fragments: the email, SMS and push flows brands pay it to run 4.
Insiders net-sold $199.9 million as growth halved
Insiders sold $200.2 million of Klaviyo stock over the 12 months to early October and bought $0.3 million, a net $199.9 million out the door 5. The company cut roles in design and product on October 1 6. Revenue still grows, just more slowly each year: 47.5% year over year in Q3 2023, 26.4% in Q2 2026, and the street models 22.2% for the quarter due on November 4 at a $379.87 million consensus 78.
Klaviyo's growth has halved in three years; the street models 22% for Q3
- Revenue growth, year over year
- Estimate
Data
| Revenue growth, year over year | |
|---|---|
| Q3 '23 | 47.5% |
| Q4 '23 | 38.8% |
| Q1 '24 | 34.5% |
| Q2 '24 | 35% |
| Q3 '24 | 33.7% |
| Q4 '24 | 34% |
| Q1 '25 | 33.3% |
| Q2 '25 | 31.9% |
| Q3 '25 | 32.2% |
| Q4 '25 | 29.6% |
| Q1 '26 | 27.9% |
| Q2 '26 | 26.4% |
| Q3 '26E (estimate) | 22.2% |
The shares closed at $17.41 on October 7, down from a 52-week high of $33.36, against a $27.14 average brokerage target 58. GuruFocus puts fair value at $43.08; the same service scores Klaviyo's growth outlook 0 of 10 and its financial strength 8 of 10 5.
Klaviyo trades at $17.41, roughly half the $43.08 fair value GuruFocus models
- Estimate
Data
| Value | |
|---|---|
| Share price, Oct 7 | $17.41 |
| 52-week high | $33.36 |
| Average brokerage target (estimate) | $27.14 |
| GuruFocus fair value | $43.08 |
Klaviyo is selling both sides of the shift
The bull case is not hollow. In September Klaviyo went headless: 260-plus tools built on MCP, the Model Context Protocol, and 490-plus APIs now open its platform to Claude, ChatGPT or any other agent, and its own Customer Agent has exchanged more than 1.3 million messages with shoppers 4. It sells brands the messages that reach customers and the agents that serve them, and it took a seat at the protocol's design table rather than fight the rails.
The rails are also early. Amazon−0.56% — Amazon, down 0.56 percent today and Anthropic$350B — Anthropic, private, latest valuation $350B are absent from the founding group, OpenAI$1.18T — OpenAI, private, latest valuation $1.18T appears on the design list but not among the founders, and survey data cited by Forkast puts the share of US adults who trust AI agents to complete purchases at 3% 92.
Two dates will price it
The v0.1 specification and a reference implementation are due by the end of October 3. Earnings follow on November 4 8. Klaviyo is betting that knowing the customer outearns reaching them, and Poppy is the first priced test of that bet.
Deepdive
AI-generated from this story and its cited sources. Not investment advice.
