Stephen P Casper
CIK 1296969 · View on SEC EDGAR ↗
First SEC filing: Nov. 19, 2004 · Latest: Feb. 6, 2019
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Insider transactions
Price change vs current quote, split-adjusted for corporate actions since the filing — not benchmarked, not annualized, not size-weighted
| Date | Ticker | Code | Shares | Price | Value | Owned after | Δ own | A/D | vs now |
|---|---|---|---|---|---|---|---|---|---|
| Sept. 8, 2025 | MKTX | S | 1,600 | $186.59 | $298,544 | 43,208 Indirect | -3.57% | Disposed | -13.2% (price as of 2026-08-19) |
| Sept. 6, 2024 | MKTX | S | 1,000 | $259.39 | $259,390 | 9,201 Direct | -9.80% | Disposed | -37.5% (price as of 2026-08-19) |
| June 7, 2024 | MKTX | S | 500 | $199.48 | $99,740 | 10,201 Direct | -4.67% | Disposed | -18.8% (price as of 2026-08-19) |
| Dec. 15, 2020 | MKTX | S | 750 | $554.96 | $416,220 | 10,600 Direct | -6.61% | Disposed | -70.8% (price as of 2026-08-19) |
| Aug. 27, 2020 | MKTX | S | 500 | $500.00 | $250,000 | 11,350 Direct | -4.22% | Disposed | -67.6% (price as of 2026-08-19) |
| May 5, 2020 | MKTX | S | 200 | $480.98 | $96,196 | 11,567 Direct | -1.70% | Disposed | -66.3% (price as of 2026-08-19) |
| May 5, 2020 | MKTX | S | 1,400 | $479.86 | $671,804 | 11,767 Direct | -10.63% | Disposed | -66.2% (price as of 2026-08-19) |
| May 5, 2020 | MKTX | S | 200 | $477.84 | $95,568 | 13,167 Direct | -1.50% | Disposed | -66.1% (price as of 2026-08-19) |
| May 5, 2020 | MKTX | S | 200 | $476.53 | $95,306 | 13,367 Direct | -1.47% | Disposed | -66.0% (price as of 2026-08-19) |
| Sept. 3, 2019 | MKTX | S | 1,000 | $402.82 | $402,820 | 42,808 Indirect | -2.28% | Disposed | -59.8% (price as of 2026-08-19) |
| June 7, 2019 | MKTX | S | 102 | $337.30 | $34,405 | 13,055 Direct | -0.78% | Disposed | -52.0% (price as of 2026-08-19) |
| Nov. 29, 2017 | MKTX | S | 2,000 | $195.84 | $391,680 | 53,076 Direct | -3.63% | Disposed | -17.3% (price as of 2026-08-19) |
| May 17, 2017 | MKTX | S | 230 | $184.70 | $42,481 | 50,234 Direct | -0.46% | Disposed | -12.3% (price as of 2026-08-19) |
| May 9, 2016 | MKTX | S | 365 | $127.69 | $46,607 | 48,501 Direct | -0.75% | Disposed | 26.9% (price as of 2026-08-19) |
| Dec. 7, 2015 | MKTX | S | 1,500 | $112.40 | $168,600 | 43,866 Direct | -3.31% | Disposed | 44.2% (price as of 2026-08-19) |
| Feb. 10, 2015 | MKTX | S | 630 | $80.35 | $50,620 | 44,329 Direct | -1.40% | Disposed | 101.7% (price as of 2026-08-19) |
| Dec. 8, 2014 | MKTX | S | 2,000 | $69.06 | $138,120 | 39,959 Direct | -4.77% | Disposed | 134.6% (price as of 2026-08-19) |
| Sept. 8, 2014 | MKTX | S | 1,500 | $59.48 | $89,220 | 41,959 Direct | -3.45% | Disposed | 172.4% (price as of 2026-08-19) |
| July 30, 2014 | MKTX | S | 1,930 | $57.05 | $110,106 | 41,499 Direct | -4.44% | Disposed | 184.0% (price as of 2026-08-19) |
| May 5, 2011 | MKTX | P | 170 | $22.20 | $3,774 | 25,996 Direct | +0.66% | Acquired | 629.9% (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 |
|---|---|---|---|---|---|---|---|
| June 7, 2019 | MKTX | Stock Option (right to buy) | Common Stock (3,187) | $10.77 | July 30, 2019 | 3,187 | Disposed |
| Nov. 29, 2017 | MKTX | Stock Option (right to buy) | Common Stock (4,225) | $9.72 | Aug. 1, 2018 | 4,225 | Disposed |
| May 17, 2017 | MKTX | Employee Stock Option (right to buy) | Common Stock (2,500) | $16.99 | Aug. 3, 2017 | 2,500 | Disposed |
| May 9, 2016 | MKTX | Employee Stock Option (right to buy) | Common Stock (5,000) | $9.30 | Aug. 4, 2016 | 5,000 | Disposed |
| Feb. 10, 2015 | MKTX | Employee Stock Option (right to buy) | Common Stock (5,000) | $10.04 | Aug. 15, 2015 | 5,000 | Disposed |
| July 30, 2014 | MKTX | Employee Stock Option (right to buy) | Common Stock (10,000) | $11.00 | Nov. 4, 2014 | 10,000 | Disposed |
| July 30, 2009 | MKTX | Employee Stock Option (right to buy) | Common Stock (3,187) | $10.77 | July 30, 2019 | 3,187 | Acquired |
| Aug. 1, 2008 | MKTX | Non-Qualified Stock Option (right to buy) | Common Stock (4,225) | $9.72 | Aug. 1, 2018 | 4,225 | Acquired |
| Aug. 3, 2007 | MKTX | Employee Stock Option (right to buy) | Common Stock (2,500) | $16.99 | Aug. 3, 2017 | 2,500 | Acquired |
| Aug. 4, 2006 | MKTX | Employee Stock Option (right to buy) | Common Stock (5,000) | $9.30 | Aug. 4, 2016 | 5,000 | Acquired |
| Aug. 15, 2005 | MKTX | Employee Stock Option (right to buy) | Common Stock (5,000) | $10.04 | Aug. 15, 2015 | 5,000 | 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 |
|---|---|---|---|---|
| Nov. 19, 2004 | MKTX | Stock Option (right to buy)→ Common Stock, par value $0.003 (10,000) | 10,000 | Direct |