Fastly, Inc.
US ˙ NasdaqGS ˙ US31188V1008

SecurityFSLY / Fastly, Inc.
InstitutionRenaissance Technologies Llc
ManagerJames Simons
Latest Disclosed Ownership518,354 shares
Latest Disclosed Value $ 15,063,367
Renaissance Technologies Llc reports 18.68% decrease in ownership of FSLY / Fastly, Inc.

On May 14, 2026 - Renaissance Technologies Llc filed a 13F-HR form disclosing ownership of 518,354 shares of Fastly, Inc. (US:FSLY) valued at $15,063,367 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 637,454 shares of Fastly, Inc.. This represents a change in shares of -18.68% during the quarter. The current value of the position is $9,366,657 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 FASTLY CL A 31188V100 518,354 -119,100 -18.68 15,063 132.13 0.0236
2026-02-12 2025-12-31 13F FASTLY CL A 31188V100 637,454 268,213 72.64 6,489 105.54 0.0101
2025-11-13 2025-09-30 13F FASTLY CL A 31188V100 369,241 250,500 210.96 3,157 276.73 0.0042
2025-08-13 2025-06-30 13F FASTLY CL A 31188V100 118,741 118,741 838 0.0011
2024-02-13 2023-12-31 13F FASTLY CL A 31188V100 0 -531,100 -100.00 0 -100.00
2023-11-14 2023-09-30 13F FASTLY CL A 31188V100 531,100 -103,100 -16.26 10 0.00 0.0174
2023-08-11 2023-06-30 13F FASTLY CL A 31188V100 634,200 634,200 10 0.0144
2023-05-12 2023-03-31 13F FASTLY CL A 31188V100 0 -14,300 -100.00 0 0.0000
2023-02-13 2022-12-31 13F FASTLY CL A 31188V100 14,300 -1,200 -7.74 0 -100.00 0.0002
2022-11-14 2022-09-30 13F FASTLY CL A 31188V100 15,500 -1,405,503 -98.91 142 -99.14 0.0002
2022-08-12 2022-06-30 13F FASTLY CL A 31188V100 1,421,003 194,203 15.83 16,498 -22.62 0.0195
2022-05-13 2022-03-31 13F FASTLY CL A 31188V100 1,226,800 1,226,800 21,322 0.0250
2021-02-10 2020-12-31 13F FASTLY CL A 31188V100 0 -670,700 -100.00 0 -100.00
2020-11-13 2020-09-30 13F FASTLY CL A 31188V100 670,700 580,000 639.47 62,831 713.77 0.0627
2020-08-13 2020-06-30 13F FASTLY CL A 31188V100 90,700 90,700 7,721 0.0067
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.