Robert L Clark

CIK 1479324 · View on SEC EDGAR ↗

Insider

First SEC filing: Jan. 6, 2010 · Latest: May 21, 2026

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Insider at

Insider transactions

0 buys (P) 0 sells (S) Net: $0 + 99 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

99 other filings hidden
Date Ticker Code Shares Price Value Owned after Δ own A/D vs now
May 14, 2012 MTX P 200 $64.21 $12,842 200 Direct — Acquired 127.1% (price as of 2026-08-19)

Showing latest 100 of 101 transactions

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 18, 2026 MTX PHANTOM STOCK UNITS COMMON STOCK (51) — — 51 Acquired
May 20, 2026 MTX PHANTOM STOCK UNITS COMMON STOCK (1,908) — — 1,908 Acquired
March 6, 2026 MTX PHANTOM STOCK UNITS COMMON STOCK (56) — — 56 Acquired
Dec. 4, 2025 MTX PHANTOM STOCK UNITS COMMON STOCK (65) — — 65 Acquired
Sept. 5, 2025 MTX PHANTOM STOCK UNITS COMMON STOCK (54) — — 54 Acquired
June 12, 2025 MTX PHANTOM STOCK UNITS COMMON STOCK (62) — — 62 Acquired
May 14, 2025 MTX PHANTOM STOCK UNITS COMMON STOCK (2,500) — — 2,500 Acquired
March 7, 2025 MTX PHANTOM STOCK UNITS COMMON STOCK (47) — — 47 Acquired
Dec. 5, 2024 MTX PHANTOM STOCK UNITS COMMON STOCK (40) — — 40 Acquired
Sept. 6, 2024 MTX PHANTOM STOCK UNITS COMMON STOCK (40) — — 40 Acquired
June 13, 2024 MTX PHANTOM STOCK UNITS COMMON STOCK (35) — — 35 Acquired
May 15, 2024 MTX PHANTOM STOCK UNITS COMMON STOCK (1,542) — — 1,542 Acquired
March 7, 2024 MTX PHANTOM STOCK UNITS COMMON STOCK (37) — — 37 Acquired
Dec. 7, 2023 MTX PHANTOM STOCK UNITS COMMON STOCK (43) — — 43 Acquired
Oct. 2, 2023 MTX PHANTOM STOCK UNITS COMMON STOCK (61) — — 61 Acquired
Sept. 8, 2023 MTX PHANTOM STOCK UNITS COMMON STOCK (25) — — 25 Acquired
July 3, 2023 MTX PHANTOM STOCK UNITS COMMON STOCK (57) — — 57 Acquired
June 15, 2023 MTX PHANTOM STOCK UNITS COMMON STOCK (24) — — 24 Acquired
May 17, 2023 MTX PHANTOM STOCK UNITS COMMON STOCK (2,067) — — 2,067 Acquired
April 3, 2023 MTX PHANTOM STOCK UNITS COMMON STOCK (54) — — 54 Acquired
July 2, 2018 MTX Phantom Stock Units Common Stock (31) — — 31 Acquired
June 14, 2018 MTX Phantom Stock Units Common Stock (11) — — 11 Acquired
May 16, 2018 MTX Phantom Stock Units Common Stock — — 1,381 Acquired
May 16, 2018 MTX Phantom Stock Units Common Stock (1,344) — — 1,344 Acquired
April 2, 2018 MTX Phantom Stock Units Common Stock (36) — — 36 Acquired
March 8, 2018 MTX Phantom Stock Units Common Stock (10) — — 10 Acquired
Jan. 2, 2018 MTX Phantom Stock Units Common Stock (34) — — 34 Acquired
Dec. 8, 2017 MTX Phantom Stock Units Common Stock (11) — — 11 Acquired
Oct. 2, 2017 MTX Phantom Stock Units Common Stock (33) — — 33 Acquired
Sept. 7, 2017 MTX Phantom Stock Units Common Stock (12) — — 12 Acquired
July 3, 2017 MTX Phantom Stock Units Common Stock (32) — — 32 Acquired
June 9, 2017 MTX Phantom Stock Units Common Stock (10) — — 10 Acquired
May 17, 2017 MTX Phantom Stock Units Common Stock (1,381) — — 1,381 Acquired
April 3, 2017 MTX Phantom Stock Units Common Stock (31) — — 31 Acquired
March 9, 2017 MTX Phantom Stock Units Common Stock (9) — — 9 Acquired
Jan. 3, 2017 MTX Phantom Stock Units Common Stock (31) — — 31 Acquired
Dec. 9, 2016 MTX Phantom Stock Units Common Stock (8) — — 8 Acquired
Oct. 3, 2016 MTX Phantom Stock Units Common Stock (34) — — 34 Acquired
Sept. 8, 2016 MTX Phantom Stock Units Common Stock (9) — — 9 Acquired
July 1, 2016 MTX Phantom Stock Units Common Stock (41) — — 41 Acquired
June 9, 2016 MTX Phantom Stock Units Common Stock (11) — — 11 Acquired
May 11, 2016 MTX Phantom Stock Units Common Stock (1,496) — — 1,496 Acquired
April 1, 2016 MTX Phantom Stock Units Common Stock (42) — — 42 Acquired
March 10, 2016 MTX Phantom Stock Units Common Stock (11) — — 11 Acquired
Jan. 4, 2016 MTX Phantom Stock Units Common Stock (55) — — 55 Acquired
Dec. 10, 2015 MTX Phantom Stock Units Common Stock (10) — — 10 Acquired
Oct. 1, 2015 MTX Phantom Stock Units Common Stock (49) — — 49 Acquired
Sept. 10, 2015 MTX Phantom Stock Units Common Stock (11) — — 11 Acquired
July 1, 2015 MTX Phantom Stock Units Common Stock (35) — — 35 Acquired
June 10, 2015 MTX Phantom Stock Units Common Stock (8) — — 8 Acquired
May 13, 2015 MTX Phantom Stock Units Common Stock (1,177) — — 1,177 Acquired
April 1, 2015 MTX Phantom Stock Units Common Stock (32) — — 32 Acquired
March 11, 2015 MTX Phantom Stock Units Common Stock (7) — — 7 Acquired
Jan. 2, 2015 MTX Phantom Stock Units Common Stock (35) — — 35 Acquired
Dec. 11, 2014 MTX Phantom Stock Units Common Stock (7) — — 7 Acquired
Oct. 1, 2014 MTX Phantom Stock Units Common Stock (37) — — 37 Acquired
Sept. 11, 2014 MTX Phantom Stock Units Common Stock (8) — — 8 Acquired
July 1, 2014 MTX Phantom Stock Units Common Stock (33) — — 33 Acquired
June 11, 2014 MTX Phantom Stock Units Common Stock (8) — — 8 Acquired
May 14, 2014 MTX Phantom Stock Units Common Stock (1,276) — — 1,276 Acquired
April 1, 2014 MTX Phantom Stock Units Common Stock (38) — — 38 Acquired
March 13, 2014 MTX Phantom Stock Units Common Stock (7) — — 7 Acquired
Jan. 2, 2014 MTX Phantom Stock Units Common Stock (29) — — 29 Acquired
Dec. 12, 2013 MTX Phantom Stock Units Common Stock (7) — — 7 Acquired
Oct. 1, 2013 MTX Phantom Stock Units Common Stock (36) — — 36 Acquired
Sept. 12, 2013 MTX Phantom Stock Units Common Stock (9) — — 9 Acquired
July 1, 2013 MTX Phantom Stock Units Common Stock (42) — — 42 Acquired
June 12, 2013 MTX Phantom Stock Units Common Stock (10) — — 10 Acquired
May 15, 2013 MTX Phantom Stock Units Common Stock (1,757) — — 1,757 Acquired
April 1, 2013 MTX Phantom Stock Units Common Stock (46) — — 46 Acquired
March 13, 2013 MTX Phantom Stock Units Common Stock (8) — — 8 Acquired
Jan. 2, 2013 MTX Phantom Stock Units Common Stock (41) — — 41 Acquired
Dec. 31, 2012 MTX Phantom Stock Units Common Stock (8) — — 8 Acquired
Oct. 1, 2012 MTX Phantom Stock Units Common Stock (24) — — 24 Acquired
Sept. 13, 2012 MTX Phantom Stock Units Common Stock (2) — — 2 Acquired
July 2, 2012 MTX Phantom Stock Units Common Stock (26) — — 26 Acquired
June 13, 2012 MTX Phantom Stock Units Common Stock (3) — — 3 Acquired
May 16, 2012 MTX Phantom Stock Units Common Stock (1,021) — — 1,021 Acquired
April 2, 2012 MTX Phantom Stock Units Common Stock (24) — — 24 Acquired
March 15, 2012 MTX Phantom Stock Units Common Stock (2) — — 2 Acquired
Jan. 3, 2012 MTX Phantom Stock Units Common Stock (27) — — 27 Acquired
Dec. 15, 2011 MTX Phantom Stock Units Common Stock (2) — — 2 Acquired
Oct. 3, 2011 MTX Phantom Stock Units Common Stock (33) — — 33 Acquired
Sept. 15, 2011 MTX Phantom Stock Units Common Stock (2) — — 2 Acquired
July 1, 2011 MTX Phantom Stock Units Common Stock (23) — — 23 Acquired
June 15, 2011 MTX Phantom Stock Units Common Stock (2) — — 2 Acquired
May 18, 2011 MTX Phantom Stock Units Common Stock (905) — — 905 Acquired
April 1, 2011 MTX Phantom Stock Units Common Stock (23) — — 23 Acquired
March 16, 2011 MTX Phantom Stock Units Common Stock (1) — — 1 Acquired
Jan. 3, 2011 MTX Phantom Stock Units Common Stock (24) — — 24 Acquired
Dec. 16, 2010 MTX Phantom Stock Units Common Stock (1) — — 1 Acquired
Oct. 1, 2010 MTX Phantom Stock Units Common Stock (80) — — 80 Acquired
Sept. 16, 2010 MTX Phantom Stock Units Common Stock (1) — — 1 Acquired
July 1, 2010 MTX Phantom Stock Units Common Stock (31) — — 31 Acquired
June 16, 2010 MTX Phantom Stock Units Common Stock (1) — — 1 Acquired
May 19, 2010 MTX Phantom Stock Units Common Stock (982) — — 982 Acquired
April 1, 2010 MTX Phantom Stock Units Common Stock (27) — — 27 Acquired
March 17, 2010 MTX Phantom Stock Units Common Stock (0) — — 0 Acquired
March 17, 2010 MTX Phantom Stock Units Common Stock (0) — — 0 Acquired
Jan. 4, 2010 MTX Phantom Stock Units Common Stock (26) — — 26 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
Jan. 6, 2010 MTX Common Stock 0 Direct