Similarweb Ltd.
DE ˙ DB ˙ IL0011751653
3,56 € ↓ -0,11 (-2,94%)
2026-06-04
DEL PRIS
SecurityDE:63X / Similarweb Ltd.
InstitutionMarshall Wace, Llp
Latest Disclosed Ownership638,188 shares
Latest Disclosed Value $ 1,665,671
Marshall Wace, Llp reports 118.20% increase in ownership of 63X / Similarweb Ltd.

On May 14, 2026 - Marshall Wace, Llp filed a 13F-HR form disclosing ownership of 638,188 shares of Similarweb Ltd. (DE:63X) valued at $1,384,868 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 292,483 shares of Similarweb Ltd.. This represents a change in shares of 118.20% during the quarter. The current value of the position is $2,271,949 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)
2026-05-14 2026-03-31 13F SIMILARWEB COMMON STOCK M84137104 638,188 345,705 118.20 1,666 -23.97 0.0008
2026-02-13 2025-12-31 13F SIMILARWEB COMMON STOCK M84137104 292,483 59,269 25.41 2,191 1.01 0.0020
2025-11-13 2025-09-30 13F SIMILARWEB COMMON STOCK M84137104 233,214 62,272 36.43 2,169 61.79 0.0022
2025-08-13 2025-06-30 13F SIMILARWEB COMMON STOCK M84137104 170,942 -188,344 -52.42 1,340 -54.90 0.0015
2025-05-15 2025-03-31 13F SIMILARWEB COMMON STOCK M84137104 359,286 550 0.15 2,971 -41.55 0.0038
2025-02-13 2024-12-31 13F SIMILARWEB COMMON STOCK M84137104 358,736 66,514 22.76 5,083 96.79 0.0061
2024-11-14 2024-09-30 13F SIMILARWEB COMMON STOCK M84137104 292,222 211,804 263.38 2,583 313.94 0.0031
2024-08-14 2024-06-30 13F SIMILARWEB COMMON STOCK M84137104 80,418 -46,661 -36.72 625 -45.41 0.0008
2024-05-15 2024-03-31 13F SIMILARWEB COMMON STOCK M84137104 127,079 79,556 167.41 1,144 351.78 0.0017
2024-02-14 2023-12-31 13F SIMILARWEB COMMON STOCK M84137104 47,523 8,516 21.83 253 0.40 0.0004
2023-11-14 2023-09-30 13F SIMILARWEB COMMON STOCK M84137104 39,007 -35,419 -47.59 253 -48.36 0.0005
2023-08-14 2023-06-30 13F SIMILARWEB COMMON STOCK M84137104 74,426 4,586 6.57 488 3.39 0.0010
2023-05-15 2023-03-31 13F SIMILARWEB COMMON STOCK M84137104 69,840 46,667 201.39 472 216.78 0.0010
2023-02-14 2022-12-31 13F SIMILARWEB COMMON STOCK M84137104 23,173 -89,956 -79.52 149 -77.53 0.0003
2022-11-14 2022-09-30 13F SIMILARWEB COMMON STOCK M84137104 113,129 38,291 51.17 663 7.28 0.0015
2022-08-15 2022-06-30 13F SIMILARWEB COMMON STOCK M84137104 74,838 -65,679 -46.74 618 -65.99 0.0013
2022-05-16 2022-03-31 13F SIMILARWEB COMMON STOCK M84137104 140,517 -3,736 -2.59 1,817 -29.63 0.0034
2022-02-14 2021-12-31 13F SIMILARWEB COMMON STOCK M84137104 144,253 95,231 194.26 2,582 151.66 0.0048
2021-11-15 2021-09-30 13F SIMILARWEB COMMON STOCK M84137104 49,022 -84,417 -63.26 1,026 -60.97 0.0043
2021-08-25 2021-06-30 13F/A-1 SIMILARWEB COMMON STOCK M84137104 133,439 133,439 2,629 0.1657
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.