Klaviyo, Inc.
US ˙ NYSE ˙ US49845K1016

SecurityKVYO / Klaviyo, Inc.
InstitutionState Street Corp
Latest Disclosed Ownership1,155,820 shares
Latest Disclosed Value $ 22,492,257
State Street Corp reports 9.93% increase in ownership of KVYO / Klaviyo, Inc.

On May 15, 2026 - State Street Corp filed a 13F-HR form disclosing ownership of 1,155,820 shares of Klaviyo, Inc. (US:KVYO) valued at $22,492,257 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 1,051,455 shares of Klaviyo, Inc.. This represents a change in shares of 9.93% during the quarter. The current value of the position is $18,007,676 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F KLAVIYO COM SER A 49845K101 1,155,820 104,365 9.93 22,492 -34.12 0.0008
2026-02-13 2025-12-31 13F KLAVIYO COM SER A 49845K101 1,051,455 234,288 28.67 34,141 50.88 0.0011
2025-11-14 2025-09-30 13F KLAVIYO COM SER A 49845K101 817,167 103,360 14.48 22,627 -5.60 0.0008
2025-08-14 2025-06-30 13F KLAVIYO COM SER A 49845K101 713,807 159,831 28.85 23,970 42.99 0.0009
2025-05-15 2025-03-31 13F KLAVIYO COM SER A 49845K101 553,976 27,281 5.18 16,763 -22.82 0.0007
2025-02-14 2024-12-31 13F KLAVIYO COM SER A 49845K101 526,695 91,247 20.95 21,721 40.98 0.0009
2024-11-14 2024-09-30 13F KLAVIYO COM SER A 49845K101 435,448 32,034 7.94 15,406 53.45 0.0006
2024-08-14 2024-06-30 13F KLAVIYO COM SER A 49845K101 403,414 162,935 67.75 10,041 63.86 0.0004
2024-05-15 2024-03-31 13F KLAVIYO COM SER A 49845K101 240,479 206,379 605.22 6,127 546.99 0.0003
2024-02-14 2023-12-31 13F KLAVIYO COM SER A 49845K101 34,100 34,100 947 0.0000
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.