David Alan Ciesinski

Insider

First SEC filing: June 24, 2026 · Latest: June 24, 2026

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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.
Compensation Executive pay disclosed in company proxy statements.

Insider at

Insider transactions

0 buys (P) 0 sells (S) Net: $0 + 79 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

79 other filings hidden

Date	Ticker	Code	Shares	Price	Value	Owned after	Δ own	A/D	vs now
June 23, 2026	WTRG	A	3,666	$36.82	$134,982	16,800 Direct	+27.91%	Acquired	11.7% (price as of 2026-08-20)
Aug. 21, 2025	MZTI	A	12,881	—	—	64,851 Direct	+24.79%	Acquired	(price as of 2026-08-20)
Aug. 21, 2025	MZTI	F	5,840	$180.29	$1,052,894	59,011 Direct	-9.01%	Disposed	-35.4% (price as of 2026-08-20)
Aug. 16, 2025	MZTI	F	2,674	$180.29	$482,095	51,970 Direct	-4.89%	Disposed	-35.4% (price as of 2026-08-20)
Aug. 12, 2025	MZTI	A	8,714	—	—	8,714 Direct	—	Acquired	(price as of 2026-08-20)
June 23, 2025	WTRG	A	3,608	$37.42	$135,011	13,134 Direct	+37.88%	Acquired	9.9% (price as of 2026-08-20)
Feb. 13, 2025	MZTI	S	17,000	$191.19	$3,250,230	54,644 Direct	-23.73%	Disposed	-39.1% (price as of 2026-08-20)
Aug. 23, 2024	MZTI	A	8,467	—	—	75,483 Direct	+12.63%	Acquired	(price as of 2026-08-20)
Aug. 23, 2024	MZTI	F	3,839	$198.38	$761,581	71,644 Direct	-5.09%	Disposed	-41.3% (price as of 2026-08-20)
Aug. 17, 2024	MZTI	F	2,466	$198.38	$489,205	67,016 Direct	-3.55%	Disposed	-41.3% (price as of 2026-08-20)
Aug. 13, 2024	MZTI	A	6,981	—	—	69,482 Direct	+11.17%	Acquired	(price as of 2026-08-20)
June 21, 2024	WTRG	A	3,259	$36.82	$119,996	9,526 Direct	+52.00%	Acquired	11.7% (price as of 2026-08-20)
Feb. 29, 2024	MZTI	M	39,416	$177.99	$7,015,654	98,906 Direct	+66.26%	Acquired	-34.6% (price as of 2026-08-20)
Feb. 29, 2024	MZTI	F	2,499	$206.92	$517,093	96,407 Direct	-2.53%	Disposed	-43.7% (price as of 2026-08-20)
Feb. 29, 2024	MZTI	D	33,906	$206.92	$7,015,830	62,501 Direct	-35.17%	Disposed	-43.7% (price as of 2026-08-20)
Feb. 29, 2024	MZTI	M	39,416	$177.99	$7,015,654	0 Direct	-100.00%	Disposed	-34.6% (price as of 2026-08-20)
Feb. 23, 2024	MZTI	F	1,961	$199.81	$391,827	59,490 Direct	-3.19%	Disposed	-41.7% (price as of 2026-08-20)
Feb. 6, 2024	MZTI	M	56,569	$153.71	$8,695,221	110,923 Direct	+104.08%	Acquired	-24.2% (price as of 2026-08-20)
Feb. 6, 2024	MZTI	F	4,486	$193.29	$867,099	106,437 Direct	-4.04%	Disposed	-39.7% (price as of 2026-08-20)
Feb. 6, 2024	MZTI	D	44,986	$193.29	$8,695,344	61,451 Direct	-42.27%	Disposed	-39.7% (price as of 2026-08-20)
Feb. 6, 2024	MZTI	M	56,569	$153.71	$8,695,221	0 Direct	-100.00%	Disposed	-24.2% (price as of 2026-08-20)
Aug. 15, 2023	MZTI	A	6,943	—	—	54,354 Direct	+14.64%	Acquired	(price as of 2026-08-20)
Aug. 15, 2023	MZTI	A	361	—	—	47,772 Direct	+0.76%	Acquired	(price as of 2026-08-20)
June 20, 2023	WTRG	A	2,173	$41.42	$90,006	6,267 Direct	+53.08%	Acquired	-0.7% (price as of 2026-08-20)
March 20, 2023	WTRG	A	702	$42.76	$30,018	4,094 Direct	+20.70%	Acquired	-3.8% (price as of 2026-08-20)
Feb. 25, 2023	MZTI	F	1,449	$192.42	$278,817	46,925 Direct	-3.00%	Disposed	-39.5% (price as of 2026-08-20)
Dec. 20, 2022	WTRG	A	591	$46.56	$27,517	3,392 Direct	+21.10%	Acquired	-11.6% (price as of 2026-08-20)
Nov. 10, 2022	MZTI	S	137	$210.14	$28,789	50,462 Direct	-0.27%	Disposed	-44.6% (price as of 2026-08-20)
Nov. 10, 2022	MZTI	S	373	$208.35	$77,715	50,089 Direct	-0.74%	Disposed	-44.1% (price as of 2026-08-20)
Nov. 10, 2022	MZTI	S	1,715	$209.25	$358,864	48,374 Direct	-3.42%	Disposed	-44.3% (price as of 2026-08-20)
Nov. 8, 2022	MZTI	M	15,654	$154.48	$2,418,230	71,954 Direct	+27.80%	Acquired	-24.6% (price as of 2026-08-20)
Nov. 8, 2022	MZTI	F	1,845	$208.76	$385,162	70,109 Direct	-2.56%	Disposed	-44.2% (price as of 2026-08-20)
Nov. 8, 2022	MZTI	S	7,926	$210.01	$1,664,539	62,183 Direct	-11.31%	Disposed	-44.5% (price as of 2026-08-20)
Nov. 8, 2022	MZTI	D	11,584	$208.76	$2,418,276	50,599 Direct	-18.63%	Disposed	-44.2% (price as of 2026-08-20)
Nov. 8, 2022	MZTI	M	15,654	—	—	15,654 Direct	-50.00%	Disposed	(price as of 2026-08-20)
Sept. 20, 2022	WTRG	A	600	$45.84	$27,504	2,801 Direct	+27.26%	Acquired	-10.3% (price as of 2026-08-20)
Aug. 30, 2022	MZTI	M	15,654	$154.48	$2,418,230	85,458 Direct	+22.43%	Acquired	-24.6% (price as of 2026-08-20)
Aug. 30, 2022	MZTI	F	2,696	$172.10	$463,982	82,762 Direct	-3.15%	Disposed	-32.3% (price as of 2026-08-20)
Aug. 30, 2022	MZTI	D	25,976	$172.10	$4,470,470	56,786 Direct	-31.39%	Disposed	-32.3% (price as of 2026-08-20)
Aug. 30, 2022	MZTI	M	15,654	—	—	15,654 Direct	-50.00%	Disposed	(price as of 2026-08-20)
Aug. 30, 2022	MZTI	M	16,946	$121.09	$2,051,991	69,804 Direct	+32.06%	Acquired	-3.8% (price as of 2026-08-20)
Aug. 30, 2022	MZTI	F	2,210	$172.10	$380,341	67,594 Direct	-3.17%	Disposed	-32.3% (price as of 2026-08-20)
Aug. 30, 2022	MZTI	D	11,294	$172.10	$1,943,697	56,300 Direct	-16.71%	Disposed	-32.3% (price as of 2026-08-20)
Aug. 30, 2022	MZTI	M	16,946	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
Aug. 16, 2022	MZTI	A	7,731	—	—	53,785 Direct	+16.79%	Acquired	(price as of 2026-08-20)
June 21, 2022	WTRG	A	656	$41.92	$27,500	2,201 Direct	+42.46%	Acquired	-1.9% (price as of 2026-08-20)
March 31, 2022	WTRG	A	532	$51.66	$27,483	1,545 Direct	+52.52%	Acquired	-20.4% (price as of 2026-08-20)
Feb. 26, 2022	MZTI	F	1,169	$168.09	$196,497	46,054 Direct	-2.48%	Disposed	-30.7% (price as of 2026-08-20)
Dec. 31, 2021	WTRG	A	466	$53.65	$25,001	1,013 Direct	+85.19%	Acquired	-23.3% (price as of 2026-08-20)
Sept. 30, 2021	WTRG	A	537	$46.60	$25,024	537 Direct	—	Acquired	-11.7% (price as of 2026-08-20)
Aug. 17, 2021	MZTI	A	5,438	—	—	47,223 Direct	+13.01%	Acquired	(price as of 2026-08-20)
Feb. 27, 2021	MZTI	F	1,228	$174.67	$214,495	41,785 Direct	-2.85%	Disposed	-33.3% (price as of 2026-08-20)
Feb. 23, 2021	MZTI	A	4,326	—	—	43,013 Direct	+11.18%	Acquired	(price as of 2026-08-20)
Feb. 23, 2021	MZTI	A	39,416	—	—	39,416 Direct	—	Acquired	(price as of 2026-08-20)
Sept. 2, 2020	MZTI	M	52,927	—	—	83,688 Direct	+172.06%	Acquired	(price as of 2026-08-20)
Sept. 2, 2020	MZTI	F	6,445	$179.92	$1,159,584	77,243 Direct	-7.70%	Disposed	-35.3% (price as of 2026-08-20)
Sept. 2, 2020	MZTI	D	38,556	$179.92	$6,936,996	38,687 Direct	-49.92%	Disposed	-35.3% (price as of 2026-08-20)
Sept. 2, 2020	MZTI	M	15,653	—	—	31,308 Direct	-33.33%	Disposed	(price as of 2026-08-20)
Sept. 2, 2020	MZTI	M	33,892	—	—	16,946 Direct	-66.67%	Disposed	(price as of 2026-08-20)
Sept. 2, 2020	MZTI	M	3,382	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
June 30, 2020	MZTI	F	320	$154.99	$49,597	30,761 Direct	-1.03%	Disposed	-24.9% (price as of 2026-08-20)
June 8, 2020	MZTI	M	43,402	—	—	69,070 Direct	+169.09%	Acquired	(price as of 2026-08-20)
June 8, 2020	MZTI	F	3,438	$167.23	$574,937	65,632 Direct	-4.98%	Disposed	-30.4% (price as of 2026-08-20)
June 8, 2020	MZTI	D	34,551	$167.23	$5,777,964	31,081 Direct	-52.64%	Disposed	-30.4% (price as of 2026-08-20)
June 8, 2020	MZTI	M	36,640	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
June 8, 2020	MZTI	M	6,762	—	—	3,382 Direct	-66.66%	Disposed	(price as of 2026-08-20)
Feb. 25, 2020	MZTI	A	4,782	—	—	25,668 Direct	+22.90%	Acquired	(price as of 2026-08-20)
Feb. 25, 2020	MZTI	A	56,569	—	—	56,569 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 21, 2020	MZTI	F	750	$156.95	$117,712	20,886 Direct	-3.47%	Disposed	-25.8% (price as of 2026-08-20)
Nov. 14, 2019	MZTI	M	47,707	—	—	62,019 Direct	+333.34%	Acquired	(price as of 2026-08-20)
Nov. 14, 2019	MZTI	F	5,955	$156.06	$929,337	56,064 Direct	-9.60%	Disposed	-25.4% (price as of 2026-08-20)
Nov. 14, 2019	MZTI	D	34,428	$156.06	$5,372,834	21,636 Direct	-61.41%	Disposed	-25.4% (price as of 2026-08-20)
Nov. 14, 2019	MZTI	M	47,707	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
April 18, 2019	MZTI	F	927	$155.25	$143,917	13,385 Direct	-6.48%	Disposed	-25.0% (price as of 2026-08-20)
Feb. 26, 2019	MZTI	A	3,852	—	—	14,312 Direct	+36.83%	Acquired	(price as of 2026-08-20)
Feb. 26, 2019	MZTI	A	46,961	—	—	46,961 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 27, 2018	MZTI	A	4,047	—	—	10,460 Direct	+63.11%	Acquired	(price as of 2026-08-20)
Feb. 27, 2018	MZTI	A	50,838	—	—	50,838 Direct	—	Acquired	(price as of 2026-08-20)
June 30, 2017	MZTI	A	714	—	—	6,413 Direct	+12.53%	Acquired	(price as of 2026-08-20)
June 30, 2017	MZTI	A	10,144	—	—	10,144 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 21, 2017	MZTI	A	36,640	—	—	36,640 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 21, 2017	MZTI	A	2,591	—	—	5,699 Direct	+83.37%	Acquired	(price as of 2026-08-20)
April 18, 2016	MZTI	A	47,707	—	—	47,707 Direct	—	Acquired	(price as of 2026-08-20)
April 18, 2016	MZTI	A	3,108	—	—	3,108 Direct	—	Acquired	(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
Aug. 12, 2025	MZTI	Restricted Stock Units	Common Stock (8,714)	—	Aug. 12, 2028	8,714	Acquired
Feb. 29, 2024	MZTI	Stock Appreciation Right	Common Stock (39,416)	$177.99	Feb. 23, 2028	39,416	Disposed
Feb. 6, 2024	MZTI	Stock Appreciation Right	Common Stock (56,569)	$153.71	Feb. 25, 2027	56,569	Disposed
Nov. 8, 2022	MZTI	Stock Appreciation Right	Common Stock (15,654)	$154.48	Feb. 26, 2024	15,654	Disposed
Aug. 30, 2022	MZTI	Stock Appreciation Right	Common Stock (15,654)	$154.48	Feb. 26, 2024	15,654	Disposed
Aug. 30, 2022	MZTI	Stock Appreciation Right	Common Stock (16,946)	$121.09	Feb. 27, 2023	16,946	Disposed
Feb. 23, 2021	MZTI	Stock Appreciation Right	Common Stock (39,416)	$177.99	Feb. 23, 2028	39,416	Acquired
Sept. 2, 2020	MZTI	Stock Appreciation Right	Common Stock (15,653)	$154.48	Feb. 26, 2024	15,653	Disposed
Sept. 2, 2020	MZTI	Stock Appreciation Right	Common Stock (33,892)	$121.09	Feb. 27, 2023	33,892	Disposed
Sept. 2, 2020	MZTI	Stock Appreciation Right	Common Stock (3,382)	$122.62	June 30, 2022	3,382	Disposed
June 8, 2020	MZTI	Stock Appreciation Right	Common Stock (36,640)	$135.06	Feb. 21, 2022	36,640	Disposed
June 8, 2020	MZTI	Stock Appreciation Right	Common Stock (6,762)	$122.62	June 30, 2022	6,762	Disposed
Feb. 25, 2020	MZTI	Stock Appreciation Right	Common Stock (56,569)	$153.71	Feb. 25, 2027	56,569	Acquired
Nov. 14, 2019	MZTI	Stock Appreciation Right	Common Stock (47,707)	$112.62	April 18, 2021	47,707	Disposed
Feb. 26, 2019	MZTI	Stock Appreciation Right	Common Stock (46,961)	$154.48	Feb. 26, 2024	46,961	Acquired
Feb. 27, 2018	MZTI	Stock Appreciation Right	Common Stock (50,838)	$121.09	Feb. 27, 2023	50,838	Acquired
June 30, 2017	MZTI	Stock Appreciation Right	Common Stock (10,144)	$122.62	June 30, 2022	10,144	Acquired
Feb. 21, 2017	MZTI	Stock Appreciation Right	Common Stock (36,640)	$17.74	Feb. 21, 2022	36,640	Acquired
April 18, 2016	MZTI	Stock Appreciation Right	Common Stock (47,707)	$13.62	April 18, 2021	47,707	Acquired

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

Compensation (DEF 14A)

Matched by name from proxy statements (DEF 14A) — verify against the filing.

MZTI

President and CEO

Fiscal year	Salary	Bonus	Stock awards	Option awards	Non-equity incentive	Pension change	Other	Total
2025	$975,000	—	—	—	$1,292,363	—	$110,885	$5,378,360
2024	$935,000	—	—	—	$1,520,404	—	$110,037	$5,415,614
2023	$890,000	—	—	—	$1,443,340	—	$96,399	$5,029,587

Figures from the Summary Compensation Table of the company's proxy statement (DEF 14A). Compensation is not a recommendation.