Similarweb Ltd.
DE ˙ DB ˙ IL0011751653
3,88 € ↑0,29 (8,07%)
2026-06-02
DEL PRIS
SecurityDE:63X / Similarweb Ltd.
InstitutionRenaissance Technologies Llc
ManagerJames Simons
Latest Disclosed Ownership739,673 shares
Latest Disclosed Value $ 1,930,547
Renaissance Technologies Llc reports 104.63% increase in ownership of 63X / Similarweb Ltd.

On May 14, 2026 - Renaissance Technologies Llc filed a 13F-HR form disclosing ownership of 739,673 shares of Similarweb Ltd. (DE:63X) valued at $1,605,090 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 361,473 shares of Similarweb Ltd.. This represents a change in shares of 104.63% during the quarter. The current value of the position is $2,872,890 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 SHS M84137104 739,673 378,200 104.63 1,931 -28.70 0.0030
2026-02-12 2025-12-31 13F SIMILARWEB SHS M84137104 361,473 -2,500 -0.69 2,707 -20.01 0.0042
2025-11-13 2025-09-30 13F SIMILARWEB SHS M84137104 363,973 8,400 2.36 3,385 21.42 0.0045
2025-08-13 2025-06-30 13F SIMILARWEB SHS M84137104 355,573 77,300 27.78 2,788 21.12 0.0037
2025-05-14 2025-03-31 13F SIMILARWEB SHS M84137104 278,273 -102,600 -26.94 2,301 -57.36 0.0035
2025-02-13 2024-12-31 13F SIMILARWEB SHS M84137104 380,873 55,873 17.19 5,397 87.82 0.0080
2024-11-13 2024-09-30 13F SIMILARWEB SHS M84137104 325,000 214,400 193.85 2,873 234.46 0.0043
2024-08-09 2024-06-30 13F SIMILARWEB SHS M84137104 110,600 4,599 4.34 859 0.0015
2024-05-13 2024-03-31 13F SIMILARWEB SHS M84137104 106,001 -19,999 -15.87 1 0.0015
2024-02-13 2023-12-31 13F SIMILARWEB SHS M84137104 126,000 90,100 250.97 1 0.0010
2023-11-14 2023-09-30 13F SIMILARWEB SHS M84137104 35,900 300 0.84 0 0.0004
2023-08-11 2023-06-30 13F SIMILARWEB SHS M84137104 35,600 4,900 15.96 0 0.0003
2023-05-12 2023-03-31 13F SIMILARWEB SHS M84137104 30,700 8,300 37.05 0 0.0003
2023-02-13 2022-12-31 13F SIMILARWEB SHS M84137104 22,400 6,400 40.00 0 -100.00 0.0002
2022-11-14 2022-09-30 13F SIMILARWEB SHS M84137104 16,000 3,500 28.00 94 -8.74 0.0001
2022-08-12 2022-06-30 13F SIMILARWEB SHS M84137104 12,500 12,500 103 0.0001
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.