Innospec Inc.
US ˙ NasdaqGS ˙ US45768S1050

SecurityIOSP / Innospec Inc.
InstitutionHolocene Advisors, LP
Latest Disclosed Ownership26,473 shares
Latest Disclosed Value $ 1,933,058
Holocene Advisors, LP reports 39.00% increase in ownership of IOSP / Innospec Inc.

On May 15, 2026 - Holocene Advisors, LP filed a 13F-HR form disclosing ownership of 26,473 shares of Innospec Inc. (US:IOSP) valued at $1,933,058 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 19,045 shares of Innospec Inc.. This represents a change in shares of 39.00% during the quarter. The current value of the position is $2,135,842 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 INNOSPEC COM 45768S105 26,473 7,428 39.00 1,933 32.67 0.0047
2026-02-17 2025-12-31 13F INNOSPEC COM 45768S105 19,045 -5,485 -22.36 1,458 -22.99 0.0031
2025-11-14 2025-09-30 13F INNOSPEC COM 45768S105 24,530 5,089 26.18 1,893 15.79 0.0043
2025-08-14 2025-06-30 13F INNOSPEC COM 45768S105 19,441 11,713 151.57 1,635 123.22 0.0040
2025-05-15 2025-03-31 13F INNOSPEC COM 45768S105 7,728 7,728 732 0.0021
2025-02-14 2024-12-31 13F INNOSPEC COM 45768S105 0 -11,123 -100.00 0 -100.00
2024-11-14 2024-09-30 13F INNOSPEC COM 45768S105 11,123 11,123 1,258 0.0051
2022-11-14 2022-09-30 13F INNOSPEC COM 45768S105 0 -6,315 -100.00 0 -100.00
2022-08-15 2022-06-30 13F INNOSPEC COM 45768S105 6,315 -3,701 -36.95 605 -34.74 0.0037
2022-05-16 2022-03-31 13F INNOSPEC COM 45768S105 10,016 -8,649 -46.34 927 -45.02 0.0048
2022-02-14 2021-12-31 13F INNOSPEC COM 45768S105 18,665 3,002 19.17 1,686 27.82 0.0088
2021-11-15 2021-09-30 13F INNOSPEC COM 45768S105 15,663 8,935 132.80 1,319 116.23 0.0072
2021-08-16 2021-06-30 13F INNOSPEC COM 45768S105 6,728 -4,003 -37.30 610 -44.65 0.0034
2021-05-17 2021-03-31 13F INNOSPEC COM 45768S105 10,731 920 9.38 1,102 23.82 0.0069
2021-02-16 2020-12-31 13F INNOSPEC COM 45768S105 9,811 9,811 890 0.0056
2019-08-14 2019-06-30 13F INNOSPEC COM 45768S105 0 -2,566 -100.00 0 -100.00
2019-05-15 2019-03-31 13F INNOSPEC COM 45768S105 2,566 2,566 214 0.0033
2019-02-14 2018-12-31 13F INNOSPEC COM 45768S105 0 -4,556 -100.00 0 -100.00
2018-11-14 2018-09-30 13F INNOSPEC COM 45768S105 4,556 4,556 350 0.0056
2018-05-15 2018-03-31 13F INNOSPEC COM 45768S105 0 -5,599 -100.00 0 -100.00
2018-02-14 2017-12-31 13F INNOSPEC COM 45768S105 5,599 5,599 395 0.0100
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.