Mark Steven Bender insider trades: Westlake (WLK) stock buys and sales
Trades on the price chart
Daily close, with an arrow on each day they bought or sold
Companies
Where Mark reports to the SEC
Open-market buys and sales
40 trades reported on SEC Form 4, newest first
| Date | Stock | Type | Shares | Price | Value | Holding | Reported |
|---|---|---|---|---|---|---|---|
| Feb 27, 2026 | WLK | ↓ Sell | 17,409 | $100.92 | $1.8M | Direct | Mar 2, 2026 (3d) |
| May 3, 2024 | WLK | ↓ Sell | 4,950 | $152.19 | $753K | Direct | May 6, 2024 (3d) |
| Mar 6, 2024 | WLK | ↓ Sell | 4,804 | $141.02 | $677K | Direct | Mar 7, 2024 (1d) |
| Feb 26, 2024 | WLK | ↓ Sell | 4,854 | $137.57 | $668K | Direct | Feb 28, 2024 (2d) |
| Mar 31, 2022 | WLK | ↓ Sell | 6,021 | $124.35 | $749K | Direct | Apr 1, 2022 (1d) |
| Mar 30, 2022 | WLK | ↓ Sell | 6,000 | $124.80 | $749K | Direct | Mar 31, 2022 (1d) |
| Mar 29, 2022 | WLK | ↓ Sell | 4,000 | $122.44 | $490K | Direct | Mar 30, 2022 (1d) |
| Mar 25, 2022 | WLK | ↓ Sell | 8,000 | $125.34 | $1.0M | Direct | Mar 28, 2022 (3d) |
| Mar 24, 2022 | WLK | ↓ Sell | 8,000 | $125.38 | $1.0M | Direct | Mar 25, 2022 (1d) |
| Mar 23, 2022 | WLK | ↓ Sell | 6,000 | $125.17 | $751K | Direct | Mar 24, 2022 (1d) |
| Nov 11, 2021 | WLK | ↓ Sell | 2,369 | $101.57 | $241K | Direct | Nov 15, 2021 (4d) |
| Nov 8, 2021 | WLK | ↓ Sell | 631 | $100.77 | $64K | Direct | Nov 10, 2021 (2d) |
| Nov 5, 2021 | WLK | ↓ Sell | 6,356 | $98.80 | $628K | Direct | Nov 8, 2021 (3d) |
| Mar 12, 2021 | WLK | ↓ Sell | 15,740 | $94.70 | $1.5M | Direct | Mar 15, 2021 (3d) |
| Mar 9, 2021 | WLK | ↓ Sell | 25,811 | $92.27 | $2.4M | Direct | Mar 10, 2021 (1d) |
| Nov 6, 2020 | WLK | ↓ Sell | 1,600 | $74.79 | $120K | Direct | Nov 10, 2020 (4d) |
| Nov 5, 2020 | WLK | ↓ Sell | 24,996 | $73.99 | $1.8M | Direct | Nov 6, 2020 (1d) |
| Mar 13, 2020 | WLKP | ↑ Buy | 2,000 | $14.99 | $30K | Direct | Mar 16, 2020 (3d) |
| May 21, 2018 | WLK | ↓ Sell | 12,066 | $122.83 | $1.5M | Direct | May 22, 2018 (1d) |
| May 11, 2018 | WLK | ↓ Sell | 23,506 | $117.33 | $2.8M | Direct | May 14, 2018 (3d) |
| Feb 27, 2018 | WLKP | ↑ Buy | 2,000 | $23.77 | $48K | Direct | Feb 27, 2018 (0d) |
| Feb 26, 2018 | WLK | ↓ Sell | 5,000 | $111.69 | $558K | Direct | Feb 27, 2018 (1d) |
| Feb 22, 2018 | WLK | ↓ Sell | 2,000 | $110.64 | $221K | Direct | Feb 26, 2018 (4d) |
| Feb 22, 2018 | WLK | ↓ Sell | 4,000 | $110.97 | $444K | Direct | Feb 23, 2018 (1d) |
| Dec 4, 2017 | WLK | ↓ Sell | 6,500 | $97.83 | $636K | Direct | Dec 5, 2017 (1d) |
| Nov 21, 2017 | WLK | ↓ Sell | 20,382 | $94.27 | $1.9M | Direct | Nov 22, 2017 (1d) |
| Nov 13, 2017 | WLK | ↓ Sell | 29,804 | $94.02 | $2.8M | Direct | Nov 15, 2017 (2d) |
| Aug 15, 2017 | WLK | ↓ Sell | 13,794 | $70.22 | $969K | Direct | Aug 16, 2017 (1d) |
| Mar 10, 2017 | WLK | ↓ Sell | 12,000 | $64.32 | $772K | Direct | Mar 13, 2017 (3d) |
| Aug 4, 2014 | WLKP | ↑ Buy | 10,000 | $24.00 | $240K | Direct | Aug 6, 2014 (2d) |
| Mar 3, 2014 | WLK | ↓ Sell | 17,721 | $133.60 | $2.4M | Direct | Mar 4, 2014 (1d) |
| Aug 12, 2013 | WLK | ↓ Sell | 2,930 | $101.00 | $296K | Direct | Aug 14, 2013 (2d) |
| Aug 8, 2013 | WLK | ↓ Sell | 3,000 | $101.00 | $303K | Direct | Aug 12, 2013 (4d) |
| Mar 25, 2013 | WLK | ↓ Sell | 4,429 | $95.00 | $421K | Direct | Mar 26, 2013 (1d) |
| Dec 3, 2012 | WLK | ↓ Sell | 6,083 | $73.25 | $446K | Direct | Dec 5, 2012 (2d) |
| Nov 26, 2012 | WLK | ↓ Sell | 4,407 | $74.86 | $330K | Direct | Nov 28, 2012 (2d) |
| Nov 23, 2012 | WLK | ↓ Sell | 1,220 | $75.95 | $93K | Direct | Nov 27, 2012 (4d) |
| Feb 25, 2011 | WLK | ↓ Sell | 27,833 | $46.47 | $1.3M | Direct | Feb 22, 2012 (362d) |
| Feb 25, 2011 | WLK | ↓ Sell | 27,833 | $46.47 | $1.3M | Direct | Feb 28, 2011 (3d) |
| Aug 9, 2010 | WLK | ↓ Sell | 1,000 | $28.17 | $28K | Direct | Aug 10, 2010 (1d) |
Each row is one filing's trades in one stock, summed. Shares and prices are as filed, before any later stock split.
Other WLK insiders
Open-market trades in the last 12 months
About Mark Steven Bender's insider trades
Mark Steven Bender is EVP & CFO at Westlake (WLK). Since Aug 9, 2010, Mark has reported 3 open-market purchases worth $318K and 37 sales worth $34.8M on SEC Form 4. In the last 12 months: 1 sale ($1.8M).
Their filings also include option exercises (40 filings), shares withheld for taxes (36 filings), grants and awards (28 filings), shares returned to the company (4 filings). These aren't open-market trades and aren't counted above.
How to read insider trades
Officers, directors and owners of more than 10% of a company must report trades in its stock on SEC Form 4, usually within two business days. Purchases with their own money are the stronger signal: insiders sell for many reasons (taxes, diversification, a house), but buy for one. See every WLK insider trade, the latest insider trades across the market, or cluster buys, when several insiders buy the same stock within days.