Plisinski Michael P

Insider

First SEC filing: Oct. 29, 2019 · Latest: Oct. 29, 2019

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

ONTO selling March 20, 2024

Insider transactions

0 buys (P) 0 sells (S) Net: $0 + 75 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

75 other filings hidden

Date	Ticker	Code	Shares	Price	Value	Owned after	Δ own	A/D	vs now
March 3, 2026	ONTO	F	3,742	$207.50	$776,465	179,242 Direct	-2.04%	Disposed	47.4% (price as of 2026-08-19)
March 2, 2026	ONTO	A	14,479	—	—	182,984 Direct	+8.59%	Acquired	(price as of 2026-08-19)
March 2, 2026	ONTO	A	7,239	—	—	7,239 Direct	—	Acquired	(price as of 2026-08-19)
March 2, 2026	ONTO	A	7,239	—	—	7,239 Direct	—	Acquired	(price as of 2026-08-19)
March 1, 2026	ONTO	M	4,597	—	—	172,652 Direct	+2.74%	Acquired	(price as of 2026-08-19)
March 1, 2026	ONTO	F	2,222	$215.89	$479,708	170,430 Direct	-1.29%	Disposed	41.7% (price as of 2026-08-19)
March 1, 2026	ONTO	F	1,925	$215.89	$415,588	168,505 Direct	-1.13%	Disposed	41.7% (price as of 2026-08-19)
March 1, 2026	ONTO	M	5,971	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-19)
Feb. 14, 2026	ONTO	M	18,445	—	—	180,606 Direct	+11.37%	Acquired	(price as of 2026-08-19)
Feb. 14, 2026	ONTO	F	8,919	$217.23	$1,937,474	171,687 Direct	-4.94%	Disposed	40.8% (price as of 2026-08-19)
Feb. 14, 2026	ONTO	F	3,632	$217.23	$788,979	168,055 Direct	-2.12%	Disposed	40.8% (price as of 2026-08-19)
Feb. 14, 2026	ONTO	M	11,824	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-19)
Dec. 24, 2025	ONTO	G	25,000	—	—	162,161 Direct	-13.36%	Disposed	(price as of 2026-08-19)
March 20, 2024	ONTO	S 10b5-1	4,344	$172.83	$750,774	271,148 Direct	-1.58%	Disposed	77.0% (price as of 2026-08-19)
March 20, 2024	ONTO	S 10b5-1	6,270	$173.96	$1,090,729	264,878 Direct	-2.31%	Disposed	75.8% (price as of 2026-08-19)
March 20, 2024	ONTO	S 10b5-1	2,060	$174.79	$360,067	262,818 Direct	-0.78%	Disposed	75.0% (price as of 2026-08-19)
March 20, 2024	ONTO	S 10b5-1	22,596	$176.00	$3,976,896	240,222 Direct	-8.60%	Disposed	73.8% (price as of 2026-08-19)
March 20, 2024	ONTO	S 10b5-1	1,816	$177.04	$321,505	238,406 Direct	-0.76%	Disposed	72.7% (price as of 2026-08-19)
March 20, 2024	ONTO	S 10b5-1	2,914	$178.16	$519,158	235,492 Direct	-1.22%	Disposed	71.7% (price as of 2026-08-19)
March 1, 2024	ONTO	A	11,943	—	—	275,492 Direct	+4.53%	Acquired	(price as of 2026-08-19)
March 1, 2024	ONTO	A	5,971	—	—	5,971 Direct	—	Acquired	(price as of 2026-08-19)
March 1, 2024	ONTO	A	5,971	—	—	5,971 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 14, 2024	ONTO	F	3,812	$173.08	$659,781	263,549 Direct	-1.43%	Disposed	76.7% (price as of 2026-08-19)
Feb. 10, 2024	ONTO	F	3,071	$180.01	$552,811	257,522 Direct	-1.18%	Disposed	69.9% (price as of 2026-08-19)
Feb. 10, 2024	ONTO	M	19,050	—	—	276,572 Direct	+7.40%	Acquired	(price as of 2026-08-19)
Feb. 10, 2024	ONTO	F	9,211	$180.01	$1,658,072	267,361 Direct	-3.33%	Disposed	69.9% (price as of 2026-08-19)
Feb. 10, 2024	ONTO	M	9,525	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-19)
Feb. 8, 2024	ONTO	F	4,032	$164.76	$664,312	247,762 Direct	-1.60%	Disposed	85.6% (price as of 2026-08-19)
Feb. 8, 2024	ONTO	M	24,834	—	—	272,596 Direct	+10.02%	Acquired	(price as of 2026-08-19)
Feb. 8, 2024	ONTO	F	12,003	$164.76	$1,977,614	260,593 Direct	-4.40%	Disposed	85.6% (price as of 2026-08-19)
Feb. 8, 2024	ONTO	M	12,417	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-19)
Aug. 21, 2023	ONTO	S 10b5-1	2,653	$110.16	$292,254	280,141 Direct	-0.94%	Disposed	177.6% (price as of 2026-08-19)
Aug. 21, 2023	ONTO	S 10b5-1	7,002	$111.86	$783,244	273,139 Direct	-2.50%	Disposed	173.4% (price as of 2026-08-19)
Aug. 21, 2023	ONTO	S 10b5-1	6,763	$112.49	$760,770	266,376 Direct	-2.48%	Disposed	171.9% (price as of 2026-08-19)
Aug. 21, 2023	ONTO	S 10b5-1	9,696	$113.76	$1,103,017	256,680 Direct	-3.64%	Disposed	168.8% (price as of 2026-08-19)
Aug. 21, 2023	ONTO	S 10b5-1	4,886	$114.44	$559,154	251,794 Direct	-1.90%	Disposed	167.2% (price as of 2026-08-19)
Feb. 14, 2023	ONTO	A	23,650	—	—	282,794 Direct	+9.13%	Acquired	(price as of 2026-08-19)
Feb. 14, 2023	ONTO	A	11,825	—	—	11,825 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 14, 2023	ONTO	A	11,824	—	—	11,824 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 10, 2023	ONTO	F	3,091	$80.90	$250,062	259,144 Direct	-1.18%	Disposed	278.0% (price as of 2026-08-19)
Feb. 8, 2023	ONTO	F	12,087	$82.30	$994,760	241,430 Direct	-4.77%	Disposed	271.6% (price as of 2026-08-19)
Feb. 8, 2023	ONTO	F	4,029	$82.30	$331,587	237,401 Direct	-1.67%	Disposed	271.6% (price as of 2026-08-19)
Feb. 8, 2023	ONTO	M	24,834	—	—	262,235 Direct	+10.46%	Acquired	(price as of 2026-08-19)
Feb. 8, 2023	ONTO	M	12,417	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-19)
Feb. 7, 2023	ONTO	F	15,189	$84.31	$1,280,585	227,423 Direct	-6.26%	Disposed	262.7% (price as of 2026-08-19)
Feb. 7, 2023	ONTO	F	5,114	$84.31	$431,161	222,309 Direct	-2.25%	Disposed	262.7% (price as of 2026-08-19)
Feb. 7, 2023	ONTO	M	31,208	—	—	253,517 Direct	+14.04%	Acquired	(price as of 2026-08-19)
Feb. 7, 2023	ONTO	M	15,604	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-19)
Feb. 10, 2022	ONTO	A	19,049	—	—	242,612 Direct	+8.52%	Acquired	(price as of 2026-08-19)
Feb. 10, 2022	ONTO	A	9,525	—	—	9,525 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 10, 2022	ONTO	A	9,524	—	—	9,524 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 8, 2022	ONTO	F	3,704	$93.09	$344,805	223,563 Direct	-1.63%	Disposed	228.5% (price as of 2026-08-19)
Feb. 7, 2022	ONTO	M	31,210	—	—	245,881 Direct	+14.54%	Acquired	(price as of 2026-08-19)
Feb. 7, 2022	ONTO	F	13,960	$90.42	$1,262,263	231,921 Direct	-5.68%	Disposed	238.2% (price as of 2026-08-19)
Feb. 7, 2022	ONTO	F	4,654	$90.42	$420,815	227,267 Direct	-2.01%	Disposed	238.2% (price as of 2026-08-19)
Feb. 7, 2022	ONTO	M	15,605	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-19)
Feb. 6, 2022	ONTO	F	2,972	$90.05	$267,629	214,671 Direct	-1.37%	Disposed	239.6% (price as of 2026-08-19)
Aug. 6, 2021	ONTO	S 10b5-1	29,592	$75.34	$2,229,461	217,643 Direct	-11.97%	Disposed	305.9% (price as of 2026-08-19)
June 16, 2021	ONTO	S 10b5-1	1,700	$75.24	$127,908	247,235 Direct	-0.68%	Disposed	306.5% (price as of 2026-08-19)
June 15, 2021	ONTO	S 10b5-1	1,800	$75.25	$135,450	248,935 Direct	-0.72%	Disposed	306.4% (price as of 2026-08-19)
June 14, 2021	ONTO	S 10b5-1	6,908	$75.30	$520,172	250,735 Direct	-2.68%	Disposed	306.1% (price as of 2026-08-19)
Feb. 8, 2021	ONTO	F	2,753	$60.40	$166,281	232,808 Direct	-1.17%	Disposed	406.3% (price as of 2026-08-19)
Feb. 8, 2021	ONTO	A	24,835	—	—	257,643 Direct	+10.67%	Acquired	(price as of 2026-08-19)
Feb. 8, 2021	ONTO	A	12,417	—	—	12,417 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 8, 2021	ONTO	A	12,417	—	—	12,417 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 7, 2021	ONTO	F	4,653	$59.95	$278,947	235,561 Direct	-1.94%	Disposed	410.1% (price as of 2026-08-19)
Feb. 6, 2021	ONTO	F	2,935	$59.95	$175,953	240,214 Direct	-1.21%	Disposed	410.1% (price as of 2026-08-19)
Jan. 27, 2021	ONTO	F	2,006	$54.83	$109,989	245,049 Direct	-0.81%	Disposed	457.8% (price as of 2026-08-19)
Jan. 27, 2021	ONTO	F	1,900	$54.83	$104,177	243,149 Direct	-0.78%	Disposed	457.8% (price as of 2026-08-19)
Nov. 4, 2020	ONTO	S 10b5-1	24,821	$35.34	$877,174	247,055 Direct	-9.13%	Disposed	765.4% (price as of 2026-08-19)
Nov. 3, 2020	ONTO	S 10b5-1	45,079	$35.22	$1,587,682	271,976 Direct	-14.22%	Disposed	768.3% (price as of 2026-08-19)
Nov. 3, 2020	ONTO	S 10b5-1	100	$36.08	$3,608	271,876 Direct	-0.04%	Disposed	747.6% (price as of 2026-08-19)
Feb. 8, 2020	ONTO	F	2,730	$38.45	$104,968	317,055 Direct	-0.85%	Disposed	695.4% (price as of 2026-08-19)
Feb. 8, 2020	ONTO	F	1,375	$38.45	$52,869	321,223 Direct	-0.43%	Disposed	695.4% (price as of 2026-08-19)
Feb. 8, 2020	ONTO	D	1,375	$38.45	$52,869	290,013 Direct	-0.47%	Disposed	695.4% (price as of 2026-08-19)
Feb. 7, 2020	ONTO	A	31,210	—	—	319,785 Direct	+10.82%	Acquired	(price as of 2026-08-19)
Feb. 7, 2020	ONTO	A	15,605	—	—	15,605 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 7, 2020	ONTO	A	15,604	—	—	15,604 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 7, 2020	ONTO	A	31,210	—	—	322,598 Direct	+10.71%	Acquired	(price as of 2026-08-19)
Feb. 7, 2020	ONTO	A	15,605	—	—	15,605 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 7, 2020	ONTO	A	15,604	—	—	15,604 Direct	—	Acquired	(price as of 2026-08-19)
Feb. 6, 2020	ONTO	F	2,760	$41.47	$114,457	291,485 Direct	-0.94%	Disposed	637.5% (price as of 2026-08-19)
Feb. 6, 2020	ONTO	F	2,910	$41.47	$120,678	288,575 Direct	-1.00%	Disposed	637.5% (price as of 2026-08-19)
Feb. 6, 2020	ONTO	F	1,391	$41.47	$57,685	292,854 Direct	-0.47%	Disposed	637.5% (price as of 2026-08-19)
Feb. 6, 2020	ONTO	F	1,466	$41.47	$60,795	291,388 Direct	-0.50%	Disposed	637.5% (price as of 2026-08-19)
Feb. 6, 2020	ONTO	D	1,391	$41.47	$57,685	292,854 Direct	-0.47%	Disposed	637.5% (price as of 2026-08-19)
Feb. 6, 2020	ONTO	D	1,466	$41.47	$60,795	291,388 Direct	-0.50%	Disposed	637.5% (price as of 2026-08-19)
Jan. 28, 2020	ONTO	D	1,076	$38.63	$41,566	295,142 Direct	-0.36%	Disposed	691.7% (price as of 2026-08-19)
Jan. 28, 2020	ONTO	D	897	$38.63	$34,651	294,245 Direct	-0.30%	Disposed	691.7% (price as of 2026-08-19)
Jan. 27, 2020	ONTO	D	1,185	$38.02	$45,054	297,549 Direct	-0.40%	Disposed	704.4% (price as of 2026-08-19)
Jan. 27, 2020	ONTO	D	1,331	$38.02	$50,605	296,218 Direct	-0.45%	Disposed	704.4% (price as of 2026-08-19)
Oct. 25, 2019	ONTO	A	62,313	—	—	298,734 Direct	+26.36%	Acquired	(price as of 2026-08-19)
Oct. 25, 2019	ONTO	A	236,421	—	—	236,421 Direct	—	Acquired	(price as of 2026-08-19)

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
March 2, 2026	ONTO	Performance Stock Unit	Common Stock (7,239)	—	March 2, 2028	7,239	Acquired
March 2, 2026	ONTO	Performance Stock Unit	Common Stock (7,239)	—	March 2, 2029	7,239	Acquired
March 1, 2026	ONTO	Performance Stock Unit	Common Stock (5,971)	—	March 1, 2026	5,971	Disposed
Feb. 14, 2026	ONTO	Performance Stock Unit	Common Stock (11,824)	—	Feb. 14, 2026	11,824	Disposed
March 1, 2024	ONTO	Performance Stock Unit	Common Stock (5,971)	—	March 1, 2026	5,971	Acquired
March 1, 2024	ONTO	Performance Stock Unit	Common Stock (5,971)	—	March 1, 2027	5,971	Acquired
Feb. 10, 2024	ONTO	Performance Stock Unit	Common Stock (9,525)	—	Feb. 10, 2024	9,525	Disposed
Feb. 8, 2024	ONTO	Performance Stock Unit	Common Stock (12,417)	—	Feb. 8, 2024	12,417	Disposed
Feb. 14, 2023	ONTO	Performance Stock Unit	Common Stock (11,825)	—	Feb. 14, 2025	11,825	Acquired
Feb. 14, 2023	ONTO	Performance Stock Unit	Common Stock (11,824)	—	Feb. 14, 2026	11,824	Acquired
Feb. 8, 2023	ONTO	Performance Stock Unit	Common Stock (12,417)	—	Feb. 8, 2023	12,417	Disposed
Feb. 7, 2023	ONTO	Performance Stock Unit	Common Stock (15,604)	—	Feb. 7, 2023	15,604	Disposed
Feb. 10, 2022	ONTO	Performance Stock Unit	Common Stock (9,525)	—	Feb. 10, 2024	9,525	Acquired
Feb. 10, 2022	ONTO	Performance Stock Unit	Common Stock (9,524)	—	Feb. 10, 2025	9,524	Acquired
Feb. 7, 2022	ONTO	Performance Stock Unit	Common Stock	—	Feb. 7, 2022	15,605	Disposed
Feb. 8, 2021	ONTO	Performance Stock Unit	Common Stock (12,417)	—	Feb. 8, 2023	12,417	Acquired
Feb. 8, 2021	ONTO	Performance Stock Unit	Common Stock (12,417)	—	Feb. 8, 2024	12,417	Acquired
Feb. 7, 2020	ONTO	Performance Stock Unit	Common Stock (15,605)	—	Feb. 7, 2022	15,605	Acquired
Feb. 7, 2020	ONTO	Performance Stock Unit	Common Stock (15,604)	—	Feb. 7, 2023	15,604	Acquired
Feb. 7, 2020	ONTO	Performance Stock Unit	Common Stock (15,605)	—	Feb. 7, 2022	15,605	Acquired
Feb. 7, 2020	ONTO	Performance Stock Unit	Common Stock (15,604)	—	Feb. 7, 2023	15,604	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. 29, 2019	ONTO	No securities beneficially owned	0	Direct