John Joseph Johnston

Insider

First SEC filing: July 29, 2021 · Latest: July 29, 2021

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

MXCT selling Dec. 26, 2023

Insider transactions

0 buys (P) 0 sells (S) Net: $0 + 29 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

29 other filings hidden

Date	Ticker	Code	Shares	Price	Value	Owned after	Δ own	A/D	vs now
June 17, 2026	MXCT	A	30,421	—	—	201,581 Direct	+17.77%	Acquired	(price as of 2026-08-20)
June 17, 2026	MXCT	A	49,579	—	—	49,579 Direct	—	Acquired	(price as of 2026-08-20)
June 18, 2025	MXCT	A	50,790	—	—	50,790 Direct	—	Acquired	(price as of 2026-08-20)
June 18, 2025	MXCT	A	29,210	—	—	171,160 Direct	+20.58%	Acquired	(price as of 2026-08-20)
Dec. 26, 2023	MXCT	M 10b5-1	5,000	—	—	15,617 Direct	-24.25%	Disposed	(price as of 2026-08-20)
Dec. 26, 2023	MXCT	S 10b5-1	5,000	$4.53	$22,650	120,583 Direct	-3.98%	Disposed	-69.2% (price as of 2026-08-20)
Dec. 26, 2023	MXCT	M 10b5-1	5,000	$2.14	$10,700	125,583 Direct	+4.15%	Acquired	-34.8% (price as of 2026-08-20)
Nov. 27, 2023	MXCT	M 10b5-1	5,000	—	—	20,617 Direct	-19.52%	Disposed	(price as of 2026-08-20)
Nov. 27, 2023	MXCT	S 10b5-1	5,000	$4.59	$22,950	120,583 Direct	-3.98%	Disposed	-69.6% (price as of 2026-08-20)
Nov. 27, 2023	MXCT	M 10b5-1	5,000	$2.14	$10,700	125,583 Direct	+4.15%	Acquired	-34.8% (price as of 2026-08-20)
Nov. 14, 2023	MXCT	M 10b5-1	1,283	—	—	25,617 Direct	-4.77%	Disposed	(price as of 2026-08-20)
Nov. 14, 2023	MXCT	M 10b5-1	8,717	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
Nov. 14, 2023	MXCT	S 10b5-1	10,000	$3.71	$37,100	120,583 Direct	-7.66%	Disposed	-62.4% (price as of 2026-08-20)
Nov. 14, 2023	MXCT	M 10b5-1	1,283	$2.14	$2,746	130,583 Direct	+0.99%	Acquired	-34.8% (price as of 2026-08-20)
Nov. 14, 2023	MXCT	M 10b5-1	8,717	$1.64	$14,296	129,300 Direct	+7.23%	Acquired	-14.9% (price as of 2026-08-20)
Aug. 30, 2023	MXCT	M 10b5-1	2,841	—	—	8,717 Direct	-24.58%	Disposed	(price as of 2026-08-20)
Aug. 30, 2023	MXCT	S 10b5-1	2,841	$3.70	$10,512	120,583 Direct	-2.30%	Disposed	-62.3% (price as of 2026-08-20)
Aug. 30, 2023	MXCT	M 10b5-1	2,841	$1.64	$4,659	123,424 Direct	+2.36%	Acquired	-14.9% (price as of 2026-08-20)
Aug. 29, 2023	MXCT	M 10b5-1	2,059	—	—	11,558 Direct	-15.12%	Disposed	(price as of 2026-08-20)
Aug. 29, 2023	MXCT	S 10b5-1	2,059	$3.70	$7,618	120,583 Direct	-1.68%	Disposed	-62.3% (price as of 2026-08-20)
Aug. 29, 2023	MXCT	M 10b5-1	2,059	$1.64	$3,377	122,642 Direct	+1.71%	Acquired	-14.9% (price as of 2026-08-20)
Aug. 28, 2023	MXCT	M 10b5-1	100	—	—	13,617 Direct	-0.73%	Disposed	(price as of 2026-08-20)
Aug. 28, 2023	MXCT	S 10b5-1	100	$3.70	$370	120,583 Direct	-0.08%	Disposed	-62.3% (price as of 2026-08-20)
Aug. 28, 2023	MXCT	M 10b5-1	100	$1.64	$164	120,683 Direct	+0.08%	Acquired	-14.9% (price as of 2026-08-20)
July 26, 2023	MXCT	M 10b5-1	5,000	—	—	13,717 Direct	-26.71%	Disposed	(price as of 2026-08-20)
July 26, 2023	MXCT	S 10b5-1	5,000	$4.75	$23,750	120,583 Direct	-3.98%	Disposed	-70.6% (price as of 2026-08-20)
July 26, 2023	MXCT	M 10b5-1	5,000	$1.64	$8,200	125,583 Direct	+4.15%	Acquired	-14.9% (price as of 2026-08-20)
June 27, 2023	MXCT	S 10b5-1	7,471	$4.39	$32,798	120,583 Direct	-5.83%	Disposed	-68.2% (price as of 2026-08-20)
June 27, 2023	MXCT	M 10b5-1	7,471	—	—	18,717 Direct	-28.53%	Disposed	(price as of 2026-08-20)
June 27, 2023	MXCT	M 10b5-1	7,471	$1.64	$12,252	128,054 Direct	+6.20%	Acquired	-14.9% (price as of 2026-08-20)
June 26, 2023	MXCT	M 10b5-1	712	—	—	26,188 Direct	-2.65%	Disposed	(price as of 2026-08-20)
June 26, 2023	MXCT	M 10b5-1	6,817	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
June 26, 2023	MXCT	S 10b5-1	7,529	$4.49	$33,805	120,583 Direct	-5.88%	Disposed	-68.9% (price as of 2026-08-20)
June 26, 2023	MXCT	M 10b5-1	712	$1.64	$1,168	128,112 Direct	+0.56%	Acquired	-14.9% (price as of 2026-08-20)
June 26, 2023	MXCT	M 10b5-1	6,817	$0.98	$6,681	127,400 Direct	+5.65%	Acquired	42.3% (price as of 2026-08-20)
June 22, 2023	MXCT	A	50,000	—	—	50,000 Direct	—	Acquired	(price as of 2026-08-20)
June 29, 2022	MXCT	A	26,900	—	—	26,900 Direct	—	Acquired	(price as of 2026-08-20)
Aug. 9, 2021	MXCT	A	10,000	—	—	10,000 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
June 17, 2026	MXCT	Stock Option (right to buy)	Common Stock (49,579)	$1.13	June 16, 2036	49,579	Acquired
June 18, 2025	MXCT	Stock Option (right to buy)	Common Stock (50,790)	$2.11	June 17, 2035	50,790	Acquired
Dec. 26, 2023	MXCT	Stock Option (right to buy)	Common Stock (5,000)	$2.14	March 4, 2029	5,000	Disposed
Nov. 27, 2023	MXCT	Stock Option (right to buy)	Common Stock (5,000)	$2.14	March 4, 2029	5,000	Disposed
Nov. 14, 2023	MXCT	Stock Option (right to buy)	Common Stock (1,283)	$2.14	March 4, 2029	1,283	Disposed
Nov. 14, 2023	MXCT	Stock Option (right to buy)	Common Stock (8,717)	$1.64	Jan. 20, 2030	8,717	Disposed
Aug. 30, 2023	MXCT	Stock Option (right to buy)	Common Stock (2,841)	$1.64	Jan. 20, 2030	2,841	Disposed
Aug. 29, 2023	MXCT	Stock Option (right to buy)	Common Stock (2,059)	$1.64	Jan. 20, 2030	2,059	Disposed
Aug. 28, 2023	MXCT	Stock Option (right to buy)	Common Stock (100)	$1.64	Jan. 20, 2030	100	Disposed
July 26, 2023	MXCT	Stock Option (right to buy)	Common Stock (5,000)	$1.64	Jan. 20, 2030	5,000	Disposed
June 27, 2023	MXCT	Stock Option (right to buy)	Common Stock (7,471)	$1.64	Jan. 20, 2030	7,471	Disposed
June 26, 2023	MXCT	Stock Option (right to buy)	Common Stock (712)	$1.64	Jan. 20, 2030	712	Disposed
June 26, 2023	MXCT	Stock Option (right to buy)	Common Stock (6,817)	$0.98	June 13, 2026	6,817	Disposed
June 22, 2023	MXCT	Stock Option (right to buy)	Common Stock (50,000)	$4.57	June 21, 2033	50,000	Acquired
June 29, 2022	MXCT	Stock Option (right to buy)	Common Stock (26,900)	$4.82	June 28, 2032	26,900	Acquired
Aug. 9, 2021	MXCT	Stock Option (right to buy)	Common Stock (10,000)	$16.63	Aug. 9, 2031	10,000	Acquired

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

Initial ownership (Form 3) 7 holdings

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

Date	Ticker	Security	Shares	Ownership
July 29, 2021	MXCT	Common Stock	120,583	Direct
July 29, 2021	MXCT	Stock Option (right to buy)→ Common Stock (6,817)	6,817	Direct
July 29, 2021	MXCT	Stock Option (right to buy)→ Common Stock (23,900)	23,900	Direct
July 29, 2021	MXCT	Stock Option (right to buy)→ Common Stock (23,900)	23,900	Direct
July 29, 2021	MXCT	Stock Option (right to buy)→ Common Stock (26,900)	26,900	Direct
July 29, 2021	MXCT	Stock Option (right to buy)→ Common Stock (26,900)	26,900	Direct
July 29, 2021	MXCT	Stock Option (right to buy)→ Common Stock (26,900)	26,900	Direct