Innospec Inc.
US ˙ NasdaqGS ˙ US45768S1050

SecurityIOSP / Innospec Inc.
InstitutionQuest Partners LLC
Latest Disclosed Ownership42,228 shares
Latest Disclosed Value $ 3,232,131
Quest Partners LLC reports 6.52% decrease in ownership of IOSP / Innospec Inc.

On February 9, 2026 - Quest Partners LLC filed a 13F-HR form disclosing ownership of 42,228 shares of Innospec Inc. (US:IOSP) valued at $3,232,131 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 3, 2025 disclosing 45,174 shares of Innospec Inc.. This represents a change in shares of -6.52% during the quarter. The current value of the position is $3,406,955 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.

Upgrade to unlock premium data and export to Excel .

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)
2026-02-09 2025-12-31 13F INNOSPEC COM 45768S105 42,228 -2,946 -6.52 3,232 -7.26 0.1809
2025-11-03 2025-09-30 13F INNOSPEC COM 45768S105 45,174 16,360 56.78 3,486 43.89 0.2278
2025-07-31 2025-06-30 13F INNOSPEC COM 45768S105 28,814 25,847 871.15 2,423 761.92 0.2380
2025-05-14 2025-03-31 13F INNOSPEC COM 45768S105 2,967 -9,689 -76.56 281 -79.81 0.0306
2025-02-07 2024-12-31 13F INNOSPEC COM 45768S105 12,656 12,352 4,063.16 1,393 3,994.12 0.1850
2024-11-07 2024-09-30 13F INNOSPEC COM 45768S105 304 -13,498 -97.80 34 -98.01 0.0031
2024-08-06 2024-06-30 13F INNOSPEC COM 45768S105 13,802 13,309 2,699.59 1,706 2,606.35 0.2314
2024-05-09 2024-03-31 13F INNOSPEC COM 45768S105 493 -1,977 -80.04 64 -79.28 0.0111
2024-02-09 2023-12-31 13F INNOSPEC COM 45768S105 2,470 2,470 304 0.0647
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.