Milton C Blackmore

Insider

First SEC filing: Oct. 8, 2010 · Latest: Oct. 8, 2010

On this page

Insider at Companies where this person is a reporting insider.
Insider transactions Every share this person bought or sold, from Form 4 filings.
Derivatives Options and other derivative holdings reported by this person.
Initial holdings The stakes this person held when they first started reporting.

Insider at

IOSP selling Feb. 27, 2026

Insider transactions

0 buys (P) 4 sells (S) Net: $-175,245 + 61 non-open-market transactions below last 12 months, based on the transactions shown below

Price change vs current quote, split-adjusted for corporate actions since the filing — not benchmarked, not annualized, not size-weighted

61 other filings hidden

Date	Ticker	Code	Shares	Price	Value	Owned after	Δ own	A/D	vs now
Feb. 27, 2026	IOSP	S	307	$76.79	$23,575	10,530 Direct	-2.83%	Disposed	20.3% (price as of 2026-08-20)
Feb. 27, 2026	IOSP	S	287	$76.30	$21,898	10,837 Direct	-2.58%	Disposed	21.0% (price as of 2026-08-20)
Feb. 27, 2026	IOSP	S	594	$76.56	$45,477	10,530 Direct	-5.34%	Disposed	20.6% (price as of 2026-08-20)
Feb. 23, 2026	IOSP	A	1,539	—	—	11,124 Direct	+16.06%	Acquired	(price as of 2026-08-20)
Feb. 20, 2026	IOSP	M	1,030	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
Feb. 20, 2026	IOSP	S	1,030	$81.84	$84,295	9,585 Direct	-9.70%	Disposed	12.8% (price as of 2026-08-20)
Feb. 20, 2026	IOSP	M	1,030	$44.18	$45,505	10,615 Direct	+10.75%	Acquired	109.0% (price as of 2026-08-20)
Feb. 24, 2025	IOSP	A	1,209	—	—	9,585 Direct	+14.43%	Acquired	(price as of 2026-08-20)
Feb. 21, 2025	IOSP	S	652	$103.30	$67,352	8,376 Direct	-7.22%	Disposed	-10.6% (price as of 2026-08-20)
Nov. 13, 2024	IOSP	M	1,035	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
Nov. 13, 2024	IOSP	S	1,035	$122.92	$127,222	9,028 Direct	-10.29%	Disposed	-24.9% (price as of 2026-08-20)
Nov. 13, 2024	IOSP	M	1,035	$43.95	$45,488	10,063 Direct	+11.46%	Acquired	110.1% (price as of 2026-08-20)
Feb. 26, 2024	IOSP	A	782	—	—	9,028 Direct	+9.48%	Acquired	(price as of 2026-08-20)
Feb. 22, 2024	IOSP	S	601	$122.07	$73,364	8,246 Direct	-6.79%	Disposed	-24.3% (price as of 2026-08-20)
Feb. 27, 2023	IOSP	A	297	—	—	297 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 27, 2023	IOSP	A	594	—	—	7,594 Direct	+8.49%	Acquired	(price as of 2026-08-20)
Feb. 25, 2022	IOSP	M	740	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
Feb. 25, 2022	IOSP	S	74	$97.53	$7,217	7,253 Direct	-1.01%	Disposed	-5.3% (price as of 2026-08-20)
Feb. 25, 2022	IOSP	S	666	$96.69	$64,396	7,327 Direct	-8.33%	Disposed	-4.5% (price as of 2026-08-20)
Feb. 25, 2022	IOSP	M	740	—	—	7,993 Direct	+10.20%	Acquired	(price as of 2026-08-20)
Feb. 21, 2022	IOSP	A	326	—	—	326 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 21, 2022	IOSP	A	652	—	—	7,253 Direct	+9.88%	Acquired	(price as of 2026-08-20)
Nov. 10, 2021	IOSP	M	293	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
Nov. 10, 2021	IOSP	S	293	$93.70	$27,454	6,601 Direct	-4.25%	Disposed	-1.4% (price as of 2026-08-20)
Nov. 10, 2021	IOSP	M	293	—	—	6,894 Direct	+4.44%	Acquired	(price as of 2026-08-20)
Feb. 22, 2021	IOSP	A	300	—	—	300 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 22, 2021	IOSP	A	601	—	—	601 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 22, 2021	IOSP	A	601	—	—	6,601 Direct	+10.02%	Acquired	(price as of 2026-08-20)
Feb. 22, 2021	IOSP	A	300	—	—	300 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 24, 2020	IOSP	A	627	—	—	627 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 24, 2020	IOSP	A	313	—	—	313 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 24, 2020	IOSP	M	283	—	—	0 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 24, 2020	IOSP	S	283	$91.75	$25,965	6,000 Direct	-4.50%	Disposed	0.7% (price as of 2026-08-20)
Feb. 24, 2020	IOSP	M	283	—	—	6,283 Direct	+4.72%	Acquired	(price as of 2026-08-20)
Feb. 25, 2019	IOSP	A	370	$81.07	$29,996	5,481 Direct	+7.24%	Acquired	13.9% (price as of 2026-08-20)
Feb. 25, 2019	IOSP	A	740	—	—	5,111 Direct	+16.93%	Acquired	(price as of 2026-08-20)
Feb. 25, 2019	IOSP	M	441	—	—	4,371 Direct	-9.16%	Disposed	(price as of 2026-08-20)
Feb. 25, 2019	IOSP	S	441	$81.62	$35,994	6,000 Direct	-6.85%	Disposed	13.1% (price as of 2026-08-20)
Feb. 25, 2019	IOSP	M	441	—	—	6,441 Direct	+7.35%	Acquired	(price as of 2026-08-20)
June 1, 2018	IOSP	M	444	—	—	4,812 Direct	-8.45%	Disposed	(price as of 2026-08-20)
June 1, 2018	IOSP	S	444	$76.83	$34,113	6,000 Direct	-6.89%	Disposed	20.2% (price as of 2026-08-20)
June 1, 2018	IOSP	M	444	—	—	6,444 Direct	+7.40%	Acquired	(price as of 2026-08-20)
Feb. 20, 2018	IOSP	A	880	$68.20	$60,016	5,256 Direct	+20.11%	Acquired	35.4% (price as of 2026-08-20)
Feb. 20, 2018	IOSP	A	293	—	—	4,376 Direct	+7.18%	Acquired	(price as of 2026-08-20)
Nov. 29, 2017	IOSP	M	977	$46.03	$44,971	4,083 Direct	-19.31%	Disposed	100.6% (price as of 2026-08-20)
Nov. 29, 2017	IOSP	S	977	$73.67	$71,976	6,000 Direct	-14.00%	Disposed	25.4% (price as of 2026-08-20)
Nov. 29, 2017	IOSP	M	977	$46.03	$44,971	6,977 Direct	+16.28%	Acquired	100.6% (price as of 2026-08-20)
Sept. 7, 2017	IOSP	P	442	$54.75	$24,200	6,000 Direct	+7.95%	Acquired	68.7% (price as of 2026-08-20)
Feb. 21, 2017	IOSP	A	283	—	—	5,060 Direct	+5.92%	Acquired	(price as of 2026-08-20)
Feb. 21, 2017	IOSP	A	850	$70.60	$60,010	4,777 Direct	+21.65%	Acquired	30.8% (price as of 2026-08-20)
Dec. 6, 2016	IOSP	M	1,089	$41.31	$44,987	3,927 Direct	-21.71%	Disposed	123.6% (price as of 2026-08-20)
Dec. 6, 2016	IOSP	S	1,089	$68.35	$74,433	5,558 Direct	-16.38%	Disposed	35.1% (price as of 2026-08-20)
Dec. 6, 2016	IOSP	M	1,089	$41.31	$44,987	6,647 Direct	+19.59%	Acquired	123.6% (price as of 2026-08-20)
Feb. 23, 2016	IOSP	M	1,522	$29.56	$44,990	3,657 Direct	-29.39%	Disposed	212.4% (price as of 2026-08-20)
Feb. 23, 2016	IOSP	M	1,380	$32.60	$44,988	5,179 Direct	-21.04%	Disposed	183.3% (price as of 2026-08-20)
Feb. 23, 2016	IOSP	F	1,026	$43.85	$44,990	5,558 Direct	-15.58%	Disposed	110.6% (price as of 2026-08-20)
Feb. 23, 2016	IOSP	M	1,522	$29.56	$44,990	6,584 Direct	+30.07%	Acquired	212.4% (price as of 2026-08-20)
Feb. 23, 2016	IOSP	F	1,026	$43.85	$44,990	5,062 Direct	-16.85%	Disposed	110.6% (price as of 2026-08-20)
Feb. 23, 2016	IOSP	M	1,380	$32.60	$44,988	6,088 Direct	+29.31%	Acquired	183.3% (price as of 2026-08-20)
Feb. 22, 2016	IOSP	A	441	—	—	5,128 Direct	+9.41%	Acquired	(price as of 2026-08-20)
Feb. 22, 2016	IOSP	A	1,030	$44.18	$45,505	4,687 Direct	+28.17%	Acquired	109.0% (price as of 2026-08-20)
Feb. 22, 2016	IOSP	A	441	—	—	5,016 Direct	+9.64%	Acquired	(price as of 2026-08-20)
Feb. 22, 2016	IOSP	A	1,030	$44.18	$45,505	4,575 Direct	+29.06%	Acquired	109.0% (price as of 2026-08-20)
Feb. 23, 2015	IOSP	A	444	—	—	6,559 Direct	+7.26%	Acquired	(price as of 2026-08-20)
Feb. 23, 2015	IOSP	A	1,035	$43.95	$45,488	6,115 Direct	+20.37%	Acquired	110.1% (price as of 2026-08-20)
Feb. 20, 2015	IOSP	M	1,000	—	—	5,080 Direct	-16.45%	Disposed	(price as of 2026-08-20)
Feb. 20, 2015	IOSP	M	1,000	—	—	4,708 Direct	+26.97%	Acquired	(price as of 2026-08-20)
Feb. 14, 2014	IOSP	A	1,089	$46.03	$50,127	6,080 Direct	+21.82%	Acquired	100.6% (price as of 2026-08-20)
July 5, 2013	IOSP	J	995	$40.18	$39,979	3,708 Direct	+36.68%	Acquired	129.8% (price as of 2026-08-20)
Feb. 20, 2013	IOSP	A	1,089	$41.31	$44,987	4,991 Direct	+27.91%	Acquired	123.6% (price as of 2026-08-20)
July 6, 2012	IOSP	J	1,350	$29.61	$39,974	2,713 Direct	+99.05%	Acquired	211.9% (price as of 2026-08-20)
July 6, 2012	IOSP	J	1,350	$26.01	$35,114	2,713 Direct	+99.05%	Acquired	255.1% (price as of 2026-08-20)
Feb. 23, 2012	IOSP	A	1,522	$29.56	$44,990	3,902 Direct	+63.95%	Acquired	212.4% (price as of 2026-08-20)
July 6, 2011	IOSP	J	297	$33.61	$9,982	1,363 Direct	+27.86%	Acquired	174.8% (price as of 2026-08-20)
May 12, 2011	IOSP	A	1,380	$32.60	$44,988	2,380 Direct	+138.00%	Acquired	183.3% (price as of 2026-08-20)
May 12, 2011	IOSP	A	1,000	—	—	1,000 Direct	—	Acquired	(price as of 2026-08-20)
July 6, 2010	IOSP	J	1,066	$9.38	$9,999	2,066 Direct	+106.60%	Acquired	884.5% (price as of 2026-08-20)

P = Open-market purchase · S = Sale · A = Grant/award · M = Option exercise · G = Gift · F = Tax withholding

Insider transactions are not a recommendation; sales are often driven by liquidity or tax reasons.

Derivative holdings (Form 4 Table II)

Options, RSUs and convertible securities reported on Form 4 Table II.

Date	Ticker	Security	Underlying	Exercise price	Expiration	Shares	A/D
Feb. 20, 2026	IOSP	Stock Option	Common Stock (1,030)	$44.18	Feb. 22, 2026	1,030	Disposed
Nov. 13, 2024	IOSP	Stock Option (Right to Buy)	Common Stock (1,035)	$43.95	Feb. 23, 2025	1,035	Disposed
Feb. 27, 2023	IOSP	Stock Option	Common Stock (297)	$109.42	Feb. 27, 2033	297	Acquired
Feb. 25, 2022	IOSP	Stock Option	Common Stock (740)	$0.00	Feb. 25, 2022	740	Disposed
Feb. 21, 2022	IOSP	Stock Option	Common Stock (326)	$99.68	Feb. 21, 2032	326	Acquired
Nov. 10, 2021	IOSP	Stock Option	Common Stock (293)	$0.00	March 15, 2022	293	Disposed
Feb. 22, 2021	IOSP	stock option	Common Stock (300)	$99.85	Feb. 22, 2031	300	Acquired
Feb. 22, 2021	IOSP	stock option	Common Stock (601)	$0.00	Feb. 22, 2024	601	Acquired
Feb. 22, 2021	IOSP	Stock Option	Common Stock (300)	$99.85	Feb. 22, 2031	300	Acquired
Feb. 24, 2020	IOSP	stock option	stock option (627)	$0.00	Feb. 24, 2023	627	Acquired
Feb. 24, 2020	IOSP	Stock Option	stock option (313)	$95.70	Feb. 24, 2030	313	Acquired
Feb. 24, 2020	IOSP	Stock Option	Common Stock (283)	$0.00	Feb. 21, 2027	283	Acquired
Feb. 25, 2019	IOSP	Stock Options	Common Stock (370)	$81.07	Feb. 25, 2029	370	Acquired
Feb. 25, 2019	IOSP	Stock Options	Common Stock (740)	$0.00	Feb. 25, 2029	740	Acquired
Feb. 25, 2019	IOSP	Stock Options	Common Stock (441)	$0.00	Feb. 25, 2026	441	Disposed
June 1, 2018	IOSP	Stock Options	Common Stock (444)	$0.00	Feb. 23, 2025	444	Disposed
Feb. 20, 2018	IOSP	Stock Option	Common Stock (880)	$68.20	Feb. 20, 2028	880	Acquired
Feb. 20, 2018	IOSP	Stock Option	Common Stock (293)	$0.00	Feb. 20, 2028	293	Acquired
Nov. 29, 2017	IOSP	Stock Options	Common Stockk (977)	$46.03	Feb. 14, 2024	977	Disposed
Feb. 21, 2017	IOSP	Stock Options	Common Stock (283)	$0.00	Feb. 21, 2027	283	Acquired
Feb. 21, 2017	IOSP	Stock Options	Common Stock (850)	$70.60	Feb. 21, 2027	850	Acquired
Dec. 6, 2016	IOSP	Stock Options	Common Stock (1,089)	$41.31	Feb. 20, 2023	1,089	Disposed
Feb. 23, 2016	IOSP	Stock Options	Common Stock (1,522)	$29.56	Feb. 23, 2022	1,522	Disposed
Feb. 23, 2016	IOSP	Stock Options	Common Stock (1,380)	$32.60	May 12, 2021	1,380	Disposed
Feb. 22, 2016	IOSP	Stock Options	Common Stock (441)	$0.00	Feb. 22, 2026	441	Acquired
Feb. 22, 2016	IOSP	Stock Options	Common Stock (1,030)	$44.18	Feb. 22, 2026	1,030	Acquired
Feb. 22, 2016	IOSP	Stock Options	Common Stock (441)	$0.00	Feb. 22, 2026	441	Acquired
Feb. 22, 2016	IOSP	Stock Options	Common Stock (1,030)	$44.18	Feb. 22, 2026	1,030	Acquired
Feb. 23, 2015	IOSP	Stock Options	Common Stock (444)	$0.00	Feb. 23, 2025	444	Acquired
Feb. 23, 2015	IOSP	Stock Options	Common Stock (1,035)	$43.95	Feb. 23, 2025	1,035	Acquired
Feb. 20, 2015	IOSP	Stock Options	Common Stock (1,000)	$0.00	May 12, 2021	1,000	Disposed
Feb. 14, 2014	IOSP	Stock Options (NEDSOP)	Common Stock (1,089)	$46.03	Feb. 14, 2024	1,089	Acquired
Feb. 20, 2013	IOSP	Stock Option (NEDSOP)	Common Stock (1,089)	$41.31	Feb. 20, 2023	1,089	Acquired
Feb. 23, 2012	IOSP	Stock Options	Common Stock (1,522)	$29.56	Feb. 23, 2022	1,522	Acquired
May 12, 2011	IOSP	Stock Options	Common Stock (1,380)	$32.60	May 12, 2021	1,380	Acquired
May 12, 2011	IOSP	Stock Options	Common Stock (1,000)	$0.00	May 12, 2021	1,000	Acquired

Exercise/conversion price is blank when not applicable (e.g. RSUs).

Initial ownership (Form 3) 1 holding

Securities held when first becoming an insider, per SEC Form 3.

Date	Ticker	Security	Shares	Ownership
Oct. 8, 2010	IOSP	Common Stock	1,000	Direct