Security Snapshot

INNOSPEC INC. - Common Stock SH (IOSP) Institutional Ownership

CUSIP: 45768S105

13F Institutional Holders and Ownership History from Q1 2014 to Q3 2026

13F reference period

Q3 2026

Institutions Reporting

168

Shares (Excl. Options)

10.92MFull value: 10,922,943 · shares · 30 Sep 2026

Price

$95.32

The headline uses the Q3 2026 reference period after its reporting deadline. Available reports may still be incomplete or amended.

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Security type / class
Equity / Common Stock SH
Symbol
IOSP on Nasdaq
All holders as of 30 Sep 2026
Q3 2026
Total 13F shares
10,922,943
Latest holder snapshot 5 signals
Total 13F value
$1,040,639,210
Portfolio coverage rank
0%
Share change
+488,282
Value change
+$51,632,883
Number of holders
168
Issuer context Names, identifiers, and filing context for this profile. 3 identity fields
Shares outstanding
24,711,085
SEC-reported price per share
$95.32
Insider filing price
$95.32
13F Shares, Excluding Options vs Price
13F Value, Excluding Options
Total Investors
Filing notes and source

Key facts

  • IOSP - INNOSPEC INC. - Common Stock SH is tracked under CUSIP 45768S105.
  • 168 institutions reported positions in Q3 2026.
  • 6 significant owners is listed from Schedule 13D/13G reporting.

Change

  • Holder count moved from 278 to 168 between Q2 2026 and Q3 2026.
  • SEC-reported value moved from
    $2BFull value: $2,001,994,680 · USD · 30 Jun 2026
    to
    $1.04BFull value: $1,040,639,210 · USD · 30 Sep 2026
    .

Research use

  • You can quickly see who holds this security, then open quarter and manager detail pages for full evidence.
  • 13F and Schedule 13D/13G sections are kept together so you can cross-check institutional and beneficial ownership context.

Evidence

Source: SEC Form 13F

Latest holder context comes from 168 institutions filings for Q3 2026.

Open SEC evidence

Security key

45768S105

13F reference period

Q3 2026

13F holders

168

13D/G owners

6

CIK / CUSIP context first

Open Q3 2026 holders IOSP full holder history INNOSPEC INC. SEC filings INNOSPEC INC. company facts INNOSPEC INC. insider transactions

Broader feeds

Latest 13F filings Latest 13D/G filings All securities

13D/G owners

Significant owners

Large-stake holder rows connected to Schedule 13D/G evidence.

Rows
6
Security
IOSP
Filer Ownership Change % Holdings Value Net Change Nb Shares Change % Reporting Name Report Period
BlackRock, Inc. 15% $330,981,773 3,681,666 BlackRock, Inc. 31 Mar 2025
VANGUARD PORTFOLIO MANAGEMENT LLC 7.5% $136,565,947 1,870,254 Vanguard Portfolio Management 31 Mar 2026
DIMENSIONAL FUND ADVISORS LP 5.3% $106,217,043 1,305,038 Dimensional Fund Advisors LP 30 Jun 2026
VANGUARD CAPITAL MANAGEMENT LLC 5.2% $94,940,166 1,300,194 Vanguard Capital Management 31 Mar 2026
Allspring Global Investments Holdings, LLC 4.7% -38% $110,701,772 -$69,680,616 1,161,421 -39% Allspring Global Investments Holdings, LLC 30 Sep 2026
WASATCH ADVISORS LP 2.1% -70% $47,480,146 -$94,572,193 528,144 -67% WASATCH ADVISORS LP 31 Mar 2025
As of 30 Sep 2026, 168 institutional investors reported holding
10.92MFull value: 10,922,943 · shares · 30 Sep 2026
shares of INNOSPEC INC. - Common Stock SH (IOSP). This represents 44% of the company’s total
24.71MFull value: 24,711,085 · shares · Stored outstanding share count
outstanding shares.

13F concentration

Top 25 institutional shareholders

Largest 13F positions for this security by reported shares and value.

Top holder share
39%
Institution Ownership % Shares Held Share Change % Portfolio % Holdings Value
VANGUARD PORTFOLIO MANAGEMENT LLC 7.6% 1,880,193 -0.21% 0.01% $179,219,997
DIMENSIONAL FUND ADVISORS LP 5.6% 1,371,706 +5.1% 0.02% $130,753,831
VANGUARD CAPITAL MANAGEMENT LLC 4.5% 1,108,786 +0.06% 0% $105,689,482
STATE STREET CORP 4.2% 1,032,465 +3.7% 0% $98,414,564
GEODE CAPITAL MANAGEMENT, LLC 2.6% 649,955 -2.5% 0% $61,965,934
WASATCH ADVISORS LP 1.4% 335,398 0.24% $31,970,137
GENDELL JEFFREY L 1.3% 324,504 0% 0.32% $30,931,721
Assenagon Asset Management S.A. 1.3% 319,633 +17% 0.03% $30,467,418
ROYCE & ASSOCIATES LP 1.2% 293,521 -4.9% 0.26% $27,978,422
Qube Research & Technologies Ltd 1.1% 277,796 -2.8% 0.03% $26,479,515
MORGAN STANLEY 1% 246,765 +6.9% 0% $23,521,673
PANAGORA ASSET MANAGEMENT INC 0.83% 204,526 +12% 0.06% $19,495,418
RENAISSANCE TECHNOLOGIES LLC 0.77% 189,900 +2.6% 0.02% $18,101,268
VANGUARD FIDUCIARY TRUST CO 0.66% 162,813 -0.55% 0% $15,519,335
MACKENZIE FINANCIAL CORP 0.57% 141,783 -2% 0.01% $13,514,756
Creative Planning 0.53% 131,473 +26% 0.01% $12,532,006
Invesco Ltd. 0.49% 121,535 +2.6% 0% $11,584,717
ProShare Advisors LLC 0.48% 118,767 +46% 0.02% $11,320,871
Leeward Investments, LLC - MA 0.48% 118,035 -5.8% 0.57% $11,251,096
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP 0.48% 117,656 +237% 0% $11,214,970
ZWJ INVESTMENT COUNSEL INC 0.47% 114,933 +5.9% 0.34% $10,955,218
DEPRINCE RACE & ZOLLO INC 0.36% 89,102 -4.5% 0.15% $8,493,203
FIRST TRUST ADVISORS LP 0.36% 88,980 -2.5% 0% $8,481,573
TEACHER RETIREMENT SYSTEM OF TEXAS 0.35% 86,741 +1.5% 0.02% $8,268,151
Public Sector Pension Investment Board 0.34% 83,749 -0.98% 0.02% $8,173,065

Quarter history

Institutional holders across reporting periods

Holder count, reported shares/value, and median price by quarter.

Periods
51
Headline period
Q3 2026
Rows shown
1-25 of 51
Period 13F Shares, Excl. Options Value, Excl. Options Value Change Price (Median) Investors
2026 Q3 10,922,943 $1,040,639,210 +$51,632,883 $95.32 168
2026 Q2 24,593,741 $2,001,994,680 -$22,755,144 $81.39 278
2026 Q1 24,941,065 $1,822,757,090 +$37,640,486 $73.02 266
2025 Q4 24,299,685 $1,859,414,311 +$40,227,383 $76.54 260
2025 Q3 23,963,379 $1,848,287,053 -$12,042,822 $77.16 264
2025 Q2 24,066,037 $2,032,008,818 -$244,646 $84.09 262
2025 Q1 23,973,835 $2,271,712,359 -$35,858,821 $94.75 270
2024 Q4 24,212,381 $2,659,279,588 +$14,644,053 $110.06 261
2024 Q3 24,105,192 $2,727,117,423 +$4,417,606 $113.09 259
2024 Q2 23,993,232 $2,964,962,134 +$1,498,648 $123.59 265
2024 Q1 23,993,573 $3,093,142,709 +$6,811,780 $128.94 236
2023 Q4 23,984,746 $2,955,807,103 +$15,777,725 $123.24 223
2023 Q3 23,846,506 $2,437,092,549 +$4,040,039 $102.20 212
2023 Q2 23,803,019 $2,390,832,044 -$7,222,988 $100.44 203
2023 Q1 23,876,871 $2,451,393,601 +$13,429,205 $102.67 218
2022 Q4 23,954,256 $2,464,210,922 -$11,084,067 $102.86 221
2022 Q3 24,019,341 $2,057,996,766 -$14,313,033 $85.67 185
2022 Q2 23,943,559 $2,293,579,459 +$28,390,916 $95.79 194
2022 Q1 23,782,835 $2,201,834,301 +$3,239,616 $92.55 179
2021 Q4 23,708,461 $2,141,965,911 -$193,662,634 $90.34 180
2021 Q3 23,443,306 $1,974,530,265 +$4,266,539 $84.22 181
2021 Q2 23,369,465 $2,117,538,766 -$19,832,760 $90.61 174
2021 Q1 23,558,548 $2,419,455,343 -$18,274,703 $102.69 175
2020 Q4 23,750,236 $2,155,050,110 +$63,786,881 $90.73 171
2020 Q3 23,235,814 $1,471,592,736 -$21,476,288 $63.32 181
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