Comparable stake leader
Bialecki Andrew
SEC ownership of Klaviyo, Inc.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001835830.
Disclosed value leader
Bialecki Andrew
Comparable rows
50/50
Latest evidence
28 Aug 2026
- Public ticker
- KVYO on NYSE
- Parsed ownership sources
-
3/4/5, 13D/G, and 13F
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
- Largest SEC-reported holder
-
Bialecki Andrew
Ranking: Comparable ownership first, then disclosed value
- Comparable ownership rows
-
50 of 50
Meaning: Rows with safely comparable ownership %
- Latest 13D/G holder
-
Bialecki Andrew
Source: Latest parsed Schedule 13D/G stake
- Latest parsed ownership date
-
28 Aug 2026
Freshness: Most recent filing date in this holder set
- Issuer CIK
- 0001835830
- Issuer location
- Boston, MA
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
3 signals
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of Klaviyo, Inc. (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
Bialecki Andrew
Disclosed value leader
Bialecki Andrew
Comparable rows
50/50
Latest evidence
28 Aug 2026
3/4/5
13D/G
13F
Lead comparable stake: 36%
13D/G row: Bialecki Andrew
Showing 1-8 of 50 holder rows.
Quick read
Bialecki Andrew leads the comparable SEC ownership view at 36%.
50 of 50 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens Bialecki Andrew's linked filing trail.
Comparable ownership
Top 5
Bialecki Andrew
36%
SHOPIFY INC.
21%
Hallen Ed
19%
SUMMIT PARTNERS L P
12%
Accomplice Fund I, L.P.
10%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-8 of 50 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Bialecki Andrew |
3/4/5
13D/G
Co-Chief Executive Officer, Director, 10%+ Owner
|
36%
from 13D/G
|
$1,477,768,228
75,326,229 shares
|
-$115,404,178 | 26 May 2026 |
| SHOPIFY INC. |
13D/G
3/4/5
Shopify Strategic Holdings 3 LLC · 10%+ Owner
|
21%
|
$590,267,180
33,405,047 shares
|
+$24,340,937 | 05 Aug 2026 |
| Hallen Ed |
13D/G
3/4/5
Director, 10%+ Owner
|
19%
|
$910,422,224
32,879,098 shares
|
$0 | 30 Sep 2025 |
| SUMMIT PARTNERS L P |
13D/G
3/4/5
13F
10%+ Owner · Company
|
12%
|
$522,033,423
18,852,778 shares
|
-$331,587,750 | 30 Sep 2025 |
| Accomplice Fund I, L.P. |
13D/G
3/4/5
Jeff Fagnan · 10%+ Owner
|
10%
|
$322,309,237
11,137,154 shares
|
$0 | 31 Mar 2025 |
| VANGUARD GROUP INC |
13D/G
The Vanguard Group
|
10%
|
$365,938,152
10,728,178 shares
|
$0 | 30 Jun 2025 |
| Capital International Investors |
13D/G
13F
Company
|
8%
|
$208,211,652
11,703,859 shares
|
-$19,301,919 | 31 Mar 2026 |
| BlackRock, Inc. |
13F
13D/G
Company
|
5.3%
from 13D/G
|
$114,942,380
7,612,078 shares
|
— | 30 Jun 2026 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
Forms 3/4/5 flow
Insider trading overview
Net insider flow leans to selling over the last 12 months. Net value: -$664,398,100.
Buys
$300,311
Insiders: 1
Sells
$664,698,411
Insiders: 13
Net
-$664,398,100
Shares: -35,577,571
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 16,339
Shares: 35,593,910
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 30,202,358 | $0 | $535,251,180 | -$535,251,180 |
| 3-6 | 0 | 1,659,486 | $0 | $28,342,768 | -$28,342,768 |
| 6-9 | 16,339 | 1,798,479 | $300,311 | $44,328,522 | -$44,028,211 |
| 9-12 | 0 | 1,933,587 | $0 | $56,775,941 | -$56,775,941 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-20 of 27 reporting-owner rows connected to Klaviyo, Inc.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
27
Largest Forms 3/4/5 holder
Bialecki Andrew
Net 12M change
-$664,398,100
Latest report
01 Sep 2026
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Bialecki Andrew | Co-Chief Executive Officer, Director, 10%+ Owner | $1,477,768,228 | -$115,404,178 | -7.2% | Mixed | 26 May 2026 |
| Astral Capital ABEH, LLC | 10%+ Owner | $147,212,115 | Mixed | 13 Feb 2024 | ||
| Gomez Luciano Fernandez | Co-Chief Executive Officer, Director | $36,306,702 | Mixed | 15 Aug 2026 | ||
| Carmel Galvin | Chief People Officer | $13,702,615 | -$306,925 | -2.2% | Median | 15 Aug 2026 |
| Stephen Eric Rowland | President | $12,603,999 | -$803,320 | -6% | Mixed | 15 Dec 2025 |
| Amanda Whalen | Chief Financial Officer | $12,013,203 | -$3,295,338 | -22% | Mixed | 14 Aug 2026 |
| Allen Chaves | Chief Technology Officer | $11,378,328 | Mixed | 16 Sep 2024 | ||
| Landon Edmond | Chief Legal Officer | $9,768,481 | -$3,122,596 | -24% | Mixed | 28 Aug 2026 |
| Hallen Ed | Director, 10%+ Owner | $8,694,498 | -$10,332,858 | -54% | Mixed | 31 Aug 2026 |
| Tony Weisman | Director | $4,342,251 | Mixed | 09 Jun 2026 | ||
| Jeff Fagnan | 10%+ Owner | $1,382,922 | Mixed | 09 Apr 2025 | ||
| Accomplice Fund I, L.P. | 10%+ Owner | $766,864 | Mixed | 23 Oct 2023 | ||
| Roxanne Oulman | Director | $748,514 | Mixed | 22 Jul 2026 | ||
| Jennifer Ceran | Director | $564,100 | +$300,311 | +114% | Mixed | 09 Jun 2026 |
| SUMMIT PARTNERS L P | 10%+ Owner | $388,278 | -$88,550,000 | -100% | Mixed | 11 Aug 2026 |
| Shopify Strategic Holdings 3 LLC | 10%+ Owner | $166,287 | Mixed | 31 Aug 2026 | ||
| Ledger Susan St. | Director | $156,099 | -$133,196 | -46% | Mixed | 09 Jun 2026 |
| SUMMIT INVESTORS GE IX/VC IV, LLC | 10%+ Owner | $0 | -$88,550,000 | -100% | Mixed | 11 Aug 2026 |
| SUMMIT INVESTORS GE IX/VC IV (UK), L.P. | 10%+ Owner | $0 | -$88,550,000 | -100% | Mixed | 11 Aug 2026 |
| Summit Partners Growth Equity Fund IX-A, L.P. | 10%+ Owner | $0 | -$88,550,000 | -100% | Mixed | 11 Aug 2026 |
Recent insider transactions for Klaviyo, Inc.
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| Ed Hallen | KVYO | Series A Common Stock | Gift | -3.84% | -17,885 | 447,746 | 31 Aug 2026 | By Hodgkins LLC | ||
| Ed Hallen | KVYO | Series A Common Stock | Sale | -11.4% | $1,221,511 | $20.49 | -59,615 | 465,631 | 31 Aug 2026 | By Hodgkins LLC |
| Ed Hallen | KVYO | Series A Common Stock | Sale | -29.3% | $801,748 | $20.47 | -39,167 | 94,457 | 31 Aug 2026 | By Hodgkins Trust |
| Landon Edmond | KVYO | Series A Common Stock | Sale | -1.67% | $165,625 | $20.44 | -8,103 | 477,866 | 31 Aug 2026 | Direct |
| Shopify Strategic Holdings 3 LLC | KVYO | Series B Common Stock | Exercise of in-the-money or at-the-money derivative security | 2.03% | 344,383 | 17,317,491 | 31 Aug 2026 | Direct | ||
| Shopify Strategic Holdings 3 LLC | KVYO | Series B Common Stock | Exercise of in-the-money or at-the-money derivative security | 2.03% | 344,383 | 17,317,491 | 31 Aug 2026 | Direct | ||
| Shopify Strategic Holdings 3 LLC | KVYO | Warrants to Purchase Series B Common Stock (Right to Buy) | Exercise of in-the-money or at-the-money derivative security | -20% | -344,383 | 1,377,529 | 31 Aug 2026 | Direct | ||
| Shopify Strategic Holdings 3 LLC | KVYO | Warrants to Purchase Series B Common Stock (Right to Buy) | Exercise of in-the-money or at-the-money derivative security | -20% | -344,383 | 1,377,529 | 31 Aug 2026 | Direct | ||
| Landon Edmond | KVYO | Series A Common Stock | Sale | -9.91% | $1,069,995 | $20.01 | -53,473 | 485,969 | 28 Aug 2026 | Direct |
| Gomez Luciano Fernandez | KVYO | Series A Common Stock | Tax liability | -1.25% | -29,133 | 2,301,573 | 15 Aug 2026 | Direct | ||
| Gomez Luciano Fernandez | KVYO | Series A Common Stock | Conversion of derivative security | 0.3% | 7,001 | 2,330,706 | 15 Aug 2026 | Direct | ||
| Gomez Luciano Fernandez | KVYO | Series B Common Stock | Conversion of derivative security | -12.5% | -7,001 | 48,999 | 15 Aug 2026 | Direct | ||
| Landon Edmond | KVYO | Series A Common Stock | Tax liability | -3.98% | -22,342 | 539,442 | 15 Aug 2026 | Direct | ||
| Carmel Galvin | KVYO | Series A Common Stock | Tax liability | -3.26% | -30,541 | 907,458 | 15 Aug 2026 | Direct | ||
| Amanda Whalen | KVYO | Series A Common Stock | Tax liability | -3.51% | -28,950 | 795,242 | 15 Aug 2026 | Direct | ||
| Amanda Whalen | KVYO | Series A Common Stock | Sale | -1.67% | $258,580 | $18.47 | -14,000 | 824,192 | 14 Aug 2026 | Direct |
| SUMMIT PARTNERS L P | KVYO | Series A Common Stock, par value $0.001 per share | Sale | -100% | $88,550,000 | $17.71 | -5,000,000 | 0 | 11 Aug 2026 | See footnotes |
| Summit Partners L P | KVYO | Series A Common Stock, par value $0.001 per share | Sale | -100% | $88,550,000 | $17.71 | -5,000,000 | 0 | 11 Aug 2026 | See footnotes |
| Summit Partners L P | KVYO | Series A Common Stock, par value $0.001 per share | Sale | -100% | $88,550,000 | $17.71 | -5,000,000 | 0 | 11 Aug 2026 | See footnotes |
| Summit Partners L P | KVYO | Series A Common Stock, par value $0.001 per share | Sale | -100% | $88,550,000 | $17.71 | -5,000,000 | 0 | 11 Aug 2026 | See footnotes |
| Summit Partners L P | KVYO | Series A Common Stock, par value $0.001 per share | Sale | -100% | $88,550,000 | $17.71 | -5,000,000 | 0 | 11 Aug 2026 | See footnotes |
| Summit Partners L P | KVYO | Series A Common Stock, par value $0.001 per share | Sale | -100% | $88,550,000 | $17.71 | -5,000,000 | 0 | 11 Aug 2026 | See footnotes |
| SUMMIT PARTNERS L P | KVYO | Series A Common Stock, par value $0.001 per share | Conversion of derivative security | 5,000,000 | 5,000,000 | 11 Aug 2026 | See footnotes | |||
| Summit Partners L P | KVYO | Series A Common Stock, par value $0.001 per share | Conversion of derivative security | 5,000,000 | 5,000,000 | 11 Aug 2026 | See footnotes | |||
| Summit Partners L P | KVYO | Series A Common Stock, par value $0.001 per share | Conversion of derivative security | 5,000,000 | 5,000,000 | 11 Aug 2026 | See footnotes | |||
| Summit Partners L P | KVYO | Series A Common Stock, par value $0.001 per share | Conversion of derivative security | 5,000,000 | 5,000,000 | 11 Aug 2026 | See footnotes | |||
| Summit Partners L P | KVYO | Series A Common Stock, par value $0.001 per share | Conversion of derivative security | 5,000,000 | 5,000,000 | 11 Aug 2026 | See footnotes | |||
| Summit Partners L P | KVYO | Series A Common Stock, par value $0.001 per share | Conversion of derivative security | 5,000,000 | 5,000,000 | 11 Aug 2026 | See footnotes | |||
| SUMMIT PARTNERS L P | KVYO | Series B Common Stock, par value $0.001 per share | Conversion of derivative security | 56.5% | 5,000,000 | 13,852,778 | 11 Aug 2026 | See footnotes | ||
| Summit Partners L P | KVYO | Series B Common Stock, par value $0.001 per share | Conversion of derivative security | 56.5% | 5,000,000 | 13,852,778 | 11 Aug 2026 | See footnotes | ||
| Summit Partners L P | KVYO | Series B Common Stock, par value $0.001 per share | Conversion of derivative security | 56.5% | 5,000,000 | 13,852,778 | 11 Aug 2026 | See footnotes | ||
| Summit Partners L P | KVYO | Series B Common Stock, par value $0.001 per share | Conversion of derivative security | 56.5% | 5,000,000 | 13,852,778 | 11 Aug 2026 | See footnotes | ||
| Summit Partners L P | KVYO | Series B Common Stock, par value $0.001 per share | Conversion of derivative security | 56.5% | 5,000,000 | 13,852,778 | 11 Aug 2026 | See footnotes | ||
| Summit Partners L P | KVYO | Series B Common Stock, par value $0.001 per share | Conversion of derivative security | 56.5% | 5,000,000 | 13,852,778 | 11 Aug 2026 | See footnotes | ||
| Roxanne Oulman | KVYO | Series A Common Stock | Conversion of derivative security | 16,775 | 16,775 | 22 Jul 2026 | By Roxanne Oulman 2025 GRAT | |||
| Roxanne Oulman | KVYO | Series B Common Stock | Conversion of derivative security | -36% | -16,775 | 29,891 | 22 Jul 2026 | By Roxanne Oulman 2025 GRAT | ||
| Amanda Whalen | KVYO | Series A Common Stock | Sale | -1.64% | $248,500 | $17.75 | -14,000 | 838,192 | 16 Jul 2026 | Direct |
| Amanda Whalen | KVYO | Series A Common Stock | Sale | -1.62% | $185,220 | $13.23 | -14,000 | 852,192 | 18 Jun 2026 | Direct |
| Roxanne Oulman | KVYO | Series A Common Stock | Conversion of derivative security | 28% | 8,169 | 37,343 | 11 Jun 2026 | Direct | ||
| Roxanne Oulman | KVYO | Series B Common Stock | Conversion of derivative security | -35% | -8,169 | 15,165 | 11 Jun 2026 | Direct | ||
| Roxanne Oulman | KVYO | Series A Common Stock | Award | 103.3% | 14,822 | 29,174 | 09 Jun 2026 | Direct | ||
| Ledger Susan St. | KVYO | Series A Common Stock | Award | 135.5% | 14,822 | 25,761 | 09 Jun 2026 | Direct | ||
| Jennifer Ceran | KVYO | Series A Common Stock | Award | 48.3% | 14,822 | 45,513 | 09 Jun 2026 | Direct | ||
| Tony Weisman | KVYO | Series A Common Stock | Award | 16.6% | 14,822 | 104,174 | 09 Jun 2026 | Direct | ||
| Gomez Luciano Fernandez | KVYO | Series A Common Stock | Tax liability | -0.08% | -1,746 | 2,323,705 | 09 Jun 2026 | Direct | ||
| Andrew Bialecki | KVYO | Series A Common Stock | Sale | -100% | $3,105,049 | $14.61 | -212,529 | 0 | 26 May 2026 | Direct |
| Andrew Bialecki | KVYO | Series A Common Stock | Conversion of derivative security | 212,529 | 212,529 | 26 May 2026 | Direct | |||
| Andrew Bialecki | KVYO | Series B Common Stock | Conversion of derivative security | -0.32% | -212,529 | 66,731,589 | 26 May 2026 | Direct | ||
| Andrew Bialecki | KVYO | Series A Common Stock | Sale | -100% | $2,976,000 | $14.88 | -200,000 | 0 | 19 May 2026 | Direct |
| Andrew Bialecki | KVYO | Series A Common Stock | Conversion of derivative security | 200,000 | 200,000 | 19 May 2026 | Direct |
* marks a reported price that did not pass the local price check.