KLA Corporation
MX ˙ BMV ˙ US4824801009
SecurityMX:KLAC / KLA Corporation
InstitutionParallax Volatility Advisers, L.P.
Latest Disclosed Ownership1,330 shares
Latest Disclosed Value $ 1,958,305
Parallax Volatility Advisers, L.P. ownership in KLAC / KLA Corporation

On May 15, 2026 - Parallax Volatility Advisers, L.P. filed a 13F-HR form disclosing ownership of 1,330 shares of KLA Corporation (MX:KLAC) valued at $1,958,305 USD as of March 31, 2026.

Parallax Volatility Advisers, L.P. has a history of taking positions in derivatives of the underlying security (KLAC) in the form of stock options. The firm currently holds call options representing 500 of underlying shares valued at $736,205 USD and put options representing 600 of underlying shares valued at $883,446 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel .

Institutional Put/Call Ratios
(Premium Subscription Required)

In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

MX:KLAC / KLA Corporation Historical Put/Call Ratio
Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F KLA COM NEW 482480100 1,330 49 3.83 1,958 25.84 0.0051
2026-02-17 2025-12-31 13F KLA COM NEW 482480100 1,281 -91 -6.63 1,557 5.21 0.0031
2025-11-14 2025-09-30 13F KLA COM NEW 482480100 1,372 1,372 1,480 0.0022
2025-08-14 2025-06-30 13F KLA COM NEW 482480100 0 -10,376 -100.00 0 -100.00
2025-05-15 2025-03-31 13F KLA COM NEW 482480100 10,376 10,376 7,054 0.0191
2024-11-14 2024-09-30 13F KLA COM NEW 482480100 0 -473 -100.00 0 -100.00
2024-08-14 2024-06-30 13F KLA COM NEW 482480100 473 -28 -5.59 390 11.46 0.0008
2024-05-15 2024-03-31 13F KLA COM NEW 482480100 501 -1,479 -74.70 350 -69.65 0.0008
2024-02-14 2023-12-31 13F KLA COM NEW 482480100 1,980 -41,324 -95.43 1,151 -94.21 0.0023
2023-11-14 2023-09-30 13F KLA COM NEW 482480100 43,304 2,781 6.86 19,862 1.05 0.0443
2023-08-14 2023-06-30 13F KLA COM NEW 482480100 40,523 3,994 10.93 19,654 34.79 0.0428
2023-05-15 2023-03-31 13F KLA COM NEW 482480100 36,529 10,530 40.50 14,581 48.76 0.0298
2023-02-27 2022-12-31 13F/A-1 KLA COM NEW 482480100 25,999 25,925 35,033.78 9,802 44,454.55 0.0152
2023-02-14 2022-12-31 13F KLA COM NEW 482480100 25,999 25,925 9,802 0.0152
2022-11-21 2022-09-30 13F/A-1 KLA COM NEW 482480100 74 60 428.57 22 450.00 0.0000
2022-11-14 2022-09-30 13F KLA COM NEW 482480100 74 60 22 0.0000
2022-08-17 2022-06-30 13F/A-1 KLA COM NEW 482480100 14 0 0.00 4 -20.00 0.0000
2022-08-15 2022-06-30 13F KLA COM NEW 482480100 14 0 4 0.0000
2022-05-16 2022-03-31 13F KLA COM NEW 482480100 14 -9,133 -99.85 5 -99.87 0.0000
2022-02-14 2021-12-31 13F/A-1 KLA COM NEW 482480100 9,147 -25,334 -73.47 3,934 -65.89 0.0100
2021-11-15 2021-09-30 13F/A-1 KLA COM NEW 482480100 34,481 -16,467 -32.32 11,534 -30.17 0.0233
2021-08-16 2021-06-30 13F/A-1 KLA COM NEW 482480100 50,948 -16,199 -24.12 16,518 -25.54 0.0226
2021-05-14 2021-03-31 13F/A-1 KLA COM NEW 482480100 67,147 42,261 169.82 22,185 244.33 0.0472
2021-02-16 2020-12-31 13F/A-1 KLA COM NEW 482480100 24,886 -38,085 -60.48 6,443 -47.19 0.0119
2020-11-13 2020-09-30 13F KLA COM NEW 482480100 62,971 36,016 133.62 12,200 132.74 0.0090
2020-08-14 2020-06-30 13F KLA COM NEW 482480100 26,955 -7,266 -21.23 5,242 6.57 0.0061
2020-05-15 2020-03-31 13F KLA COM NEW 482480100 34,221 6,272 22.44 4,919 -1.22 0.0063
2020-02-14 2019-12-31 13F KLA COM NEW 482480100 27,949 21,758 351.45 4,980 404.56 0.0057
2019-11-14 2019-09-30 13F KLA KLA CORPORATION 482480100 6,191 6,093 6,217.35 987 8,125.00 0.0011
2019-08-14 2019-06-30 13F KLA-TENCOR COM 482480100 98 -6 -5.77 12 0.00 0.0000
2019-05-15 2019-03-31 13F KLA-TENCOR COM 482480100 104 -388 -78.86 12 -72.73 0.0000
2019-02-14 2018-12-31 13F KLA-TENCOR COM 482480100 492 9 1.86 44 -10.20 0.0001
2018-11-14 2018-09-30 13F KLA-TENCOR COM 482480100 483 -39 -7.47 49 -9.26 0.0001
2018-08-14 2018-06-30 13F KLA-TENCOR COM 482480100 522 35 7.19 54 1.89 0.0001
2018-05-15 2018-03-31 13F KLA-TENCOR COM 482480100 487 -4,044 -89.25 53 -88.87 0.0001
2018-02-14 2017-12-31 13F KLA-TENCOR COM 482480100 4,531 4,518 34,753.85 476 47,500.00 0.0006
2017-11-14 2017-09-30 13F KLA-TENCOR COM 482480100 13 13 1 0.0000
2015-11-16 2015-09-30 13F KLA-TENCOR COM 482480100 0 -775 -100.00 0 -100.00
2015-08-14 2015-06-30 13F KLA-TENCOR COM 482480100 775 -2,823 -78.46 44 -79.05 0.0001
2015-05-15 2015-03-31 13F KLA-TENCOR COM 482480100 3,598 -3,272 -47.63 210 -56.52 0.0005
2015-02-17 2014-12-31 13F KLA-TENCOR COM 482480100 6,870 2,599 60.85 483 43.75 0.0014
2014-11-26 2014-09-30 13F/A-1 KLA-TENCOR COM 482480100 4,271 -63,212 -93.67 336 -93.15 0.0011
2014-11-14 2014-09-30 13F KLA-TENCOR COM 482480100 4,271 336
2014-08-14 2014-06-30 13F KLA-TENCOR COM 482480100 67,483 67,357 53,457.94 4,902 54,366.67 0.0203
2014-05-15 2014-03-31 13F KLA-TENCOR COM 482480100 126 -1,216 -90.61 9 -89.66 0.0001
2014-02-28 2013-12-31 13F/A-1 KLA-TENCOR COM 482480100 1,342 200 17.51 87 26.09 0.0004
2014-02-14 2013-12-31 13F KLA-TENCOR COM 482480100 1,342 87
2013-11-14 2013-09-30 13F KLA-TENCOR COM 482480100 1,142 -2,861 -71.47 69 -69.06 0.0004
2013-08-14 2013-06-30 13F KLA-TENCOR COM 482480100 4,003 4,003 223 0.0010
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-15 2026-03-31 13F KLA COM NEW Call 500 736 n/a n/a n/a
2025-11-14 2025-09-30 13F KLA COM NEW Call 0 -100.00 0 -100.00 n/a n/a n/a
2025-08-14 2025-06-30 13F KLA COM NEW Call 1,700 -52.78 1,523 -37.80 n/a n/a n/a
2025-05-15 2025-03-31 13F KLA COM NEW Call 3,600 -52.00 2,447 -48.21 n/a n/a n/a
2025-02-14 2024-12-31 13F KLA COM NEW Call 7,500 -33.63 4,726 -46.00 n/a n/a n/a
2024-11-14 2024-09-30 13F KLA COM NEW Call 11,300 8,751 n/a n/a n/a
2024-05-15 2024-03-31 13F KLA COM NEW Call 0 -100.00 0 -100.00 n/a n/a n/a
2024-02-14 2023-12-31 13F KLA COM NEW Call 52,400 1,178.05 30,460 1,520.21 n/a n/a n/a
2023-11-14 2023-09-30 13F KLA COM NEW Call 4,100 64.00 1,881 55.12 n/a n/a n/a
2023-08-14 2023-06-30 13F KLA COM NEW Call 2,500 -80.47 1,213 -76.28 n/a n/a n/a
2023-05-15 2023-03-31 13F KLA COM NEW Call 12,800 -89.06 5,109 -88.42 n/a n/a n/a
2023-02-27 2022-12-31 13F/A KLA COM NEW Call 117,000 65.49 44,113 106.18 n/a n/a n/a
2023-02-14 2022-12-31 13F KLA COM NEW Call 117,000 44,113 n/a n/a n/a
2022-11-21 2022-09-30 13F/A KLA COM NEW Call 70,700 244.88 21,395 226.99 n/a n/a n/a
2022-11-14 2022-09-30 13F KLA COM NEW Call 70,700 21,395 n/a n/a n/a
2022-08-17 2022-06-30 13F/A KLA COM NEW Call 20,500 -63.59 6,543 -68.25 n/a n/a n/a
2022-08-15 2022-06-30 13F KLA COM NEW Call 20,500 6,543 n/a n/a n/a
2022-05-16 2022-03-31 13F KLA COM NEW Call 56,300 10.61 20,609 -5.86 n/a n/a n/a
2022-02-14 2021-12-31 13F/A KLA COM NEW Call 50,900 -9.27 21,892 16.68 n/a n/a n/a
2021-11-15 2021-09-30 13F/A KLA COM NEW Call 56,100 312.50 18,763 325.85 n/a n/a n/a
2021-08-16 2021-06-30 13F/A KLA COM NEW Call 13,600 491.30 4,406 480.50 n/a n/a n/a
2021-05-14 2021-03-31 13F/A KLA COM NEW Call 2,300 -94.19 759 -92.60 n/a n/a n/a
2021-02-16 2020-12-31 13F/A KLA COM NEW Call 39,600 -78.44 10,254 -71.18 n/a n/a n/a
2020-11-13 2020-09-30 13F KLA COM NEW Call 183,700 177.07 35,581 176.01 n/a n/a n/a
2020-08-14 2020-06-30 13F KLA COM NEW Call 66,300 426.19 12,891 613.00 n/a n/a n/a
2020-05-15 2020-03-31 13F KLA COM NEW Call 12,600 0.80 1,808 -18.85 n/a n/a n/a
2020-02-14 2019-12-31 13F KLA COM NEW Call 12,500 -92.03 2,228 -91.09 n/a n/a n/a
2019-11-14 2019-09-30 13F KLA KLA CORPORATION Call 156,800 25,002 n/a n/a n/a
2016-02-16 2015-12-31 13F KLA-TENCOR COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2015-11-16 2015-09-30 13F KLA-TENCOR COM Call 1,100 1,000.00 55 816.67 n/a n/a n/a
2015-08-14 2015-06-30 13F KLA-TENCOR COM Call 100 -97.78 6 -97.70 n/a n/a n/a
2015-05-15 2015-03-31 13F KLA-TENCOR COM Call 4,500 -81.85 261 -85.03 n/a n/a n/a
2015-02-17 2014-12-31 13F KLA-TENCOR COM Call 24,800 -58.39 1,744 -62.85 n/a n/a n/a
2014-11-26 2014-09-30 13F/A KLA-TENCOR COM Call 59,600 893.33 4,695 979.31 n/a n/a n/a
2014-11-14 2014-09-30 13F KLA-TENCOR COM Call 59,600 4,695 n/a n/a n/a
2014-08-14 2014-06-30 13F KLA-TENCOR COM Call 6,000 53.85 435 61.11 n/a n/a n/a
2014-05-15 2014-03-31 13F KLA-TENCOR COM Call 3,900 143.75 270 162.14 n/a n/a n/a
2014-02-28 2013-12-31 13F/A KLA-TENCOR COM Call 1,600 -44.83 103 -41.48 n/a n/a n/a
2014-02-14 2013-12-31 13F KLA-TENCOR COM Call 1,600 103 n/a n/a n/a
2013-11-14 2013-09-30 13F KLA-TENCOR COM Call 2,900 2,800.00 176 2,833.33 n/a n/a n/a
2013-08-14 2013-06-30 13F KLA-TENCOR COM Call 100 6 n/a n/a n/a
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-15 2026-03-31 13F KLA COM NEW Put 600 500.00 883 629.75 n/a n/a n/a
2026-02-17 2025-12-31 13F KLA COM NEW Put 100 122 n/a n/a n/a
2025-11-14 2025-09-30 13F KLA COM NEW Put 0 -100.00 0 -100.00 n/a n/a n/a
2025-08-14 2025-06-30 13F KLA COM NEW Put 900 -94.61 806 -92.90 n/a n/a n/a
2025-05-15 2025-03-31 13F KLA COM NEW Put 16,700 -44.15 11,353 -39.75 n/a n/a n/a
2025-02-14 2024-12-31 13F KLA COM NEW Put 29,900 43.75 18,841 16.97 n/a n/a n/a
2024-11-14 2024-09-30 13F KLA COM NEW Put 20,800 177.33 16,108 160.50 n/a n/a n/a
2024-08-14 2024-06-30 13F KLA COM NEW Put 7,500 -68.88 6,184 -63.27 n/a n/a n/a
2024-05-15 2024-03-31 13F KLA COM NEW Put 24,100 -32.30 16,836 -18.65 n/a n/a n/a
2024-02-14 2023-12-31 13F KLA COM NEW Put 35,600 -6.81 20,694 18.12 n/a n/a n/a
2023-11-14 2023-09-30 13F KLA COM NEW Put 38,200 170.92 17,521 156.22 n/a n/a n/a
2023-08-14 2023-06-30 13F KLA COM NEW Put 14,100 -22.95 6,839 -6.38 n/a n/a n/a
2023-05-15 2023-03-31 13F KLA COM NEW Put 18,300 -86.48 7,305 -85.69 n/a n/a n/a
2023-02-27 2022-12-31 13F/A KLA COM NEW Put 135,400 248.07 51,050 333.43 n/a n/a n/a
2023-02-14 2022-12-31 13F KLA COM NEW Put 135,400 51,050 n/a n/a n/a
2022-11-21 2022-09-30 13F/A KLA COM NEW Put 38,900 94.50 11,778 84.38 n/a n/a n/a
2022-11-14 2022-09-30 13F KLA COM NEW Put 38,900 11,778 n/a n/a n/a
2022-08-17 2022-06-30 13F/A KLA COM NEW Put 20,000 -71.63 6,388 -75.25 n/a n/a n/a
2022-08-15 2022-06-30 13F KLA COM NEW Put 20,000 6,388 n/a n/a n/a
2022-05-16 2022-03-31 13F KLA COM NEW Put 70,500 -35.85 25,807 -45.40 n/a n/a n/a
2022-02-14 2021-12-31 13F/A KLA COM NEW Put 109,900 -0.36 47,263 28.12 n/a n/a n/a
2021-11-15 2021-09-30 13F/A KLA COM NEW Put 110,300 19.76 36,889 23.56 n/a n/a n/a
2021-08-16 2021-06-30 13F/A KLA COM NEW Put 92,100 153.02 29,854 148.31 n/a n/a n/a
2021-05-14 2021-03-31 13F/A KLA COM NEW Put 36,400 -87.87 12,023 -84.53 n/a n/a n/a
2021-02-16 2020-12-31 13F/A KLA COM NEW Put 300,200 -45.83 77,734 -27.60 n/a n/a n/a
2020-11-13 2020-09-30 13F KLA COM NEW Put 554,200 181.03 107,361 179.95 n/a n/a n/a
2020-08-14 2020-06-30 13F KLA COM NEW Put 197,200 127.45 38,350 207.78 n/a n/a n/a
2020-05-15 2020-03-31 13F KLA COM NEW Put 86,700 17.32 12,460 -5.36 n/a n/a n/a
2020-02-14 2019-12-31 13F KLA COM NEW Put 73,900 -54.35 13,166 -49.00 n/a n/a n/a
2019-11-14 2019-09-30 13F KLA KLA CORPORATION Put 161,900 25,817 n/a n/a n/a
2016-05-16 2016-03-31 13F KLA-TENCOR COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2016-02-16 2015-12-31 13F KLA-TENCOR COM Put 500 0.00 35 n/a n/a n/a
2015-11-16 2015-09-30 13F KLA-TENCOR COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2015-08-14 2015-06-30 13F KLA-TENCOR COM Put 1,100 -88.04 62 -88.41 n/a n/a n/a
2015-05-15 2015-03-31 13F KLA-TENCOR COM Put 9,200 -72.04 535 -76.85 n/a n/a n/a
2015-02-17 2014-12-31 13F KLA-TENCOR COM Put 32,900 -79.32 2,311 -81.56 n/a n/a n/a
2014-11-26 2014-09-30 13F/A KLA-TENCOR COM Put 159,100 882.10 12,533 964.83 n/a n/a n/a
2014-11-14 2014-09-30 13F KLA-TENCOR COM Put 159,100 12,533 n/a n/a n/a
2014-08-14 2014-06-30 13F KLA-TENCOR COM Put 16,200 980.00 1,177 1,031.73 n/a n/a n/a
2014-05-15 2014-03-31 13F KLA-TENCOR COM Put 1,500 200.00 104 225.00 n/a n/a n/a
2014-02-28 2013-12-31 13F/A KLA-TENCOR COM Put 500 -16.67 32 -11.11 n/a n/a n/a
2014-02-14 2013-12-31 13F KLA-TENCOR COM Put 500 32 n/a n/a n/a
2013-11-14 2013-09-30 13F KLA-TENCOR COM Put 600 20.00 36 28.57 n/a n/a n/a
2013-08-14 2013-06-30 13F KLA-TENCOR COM Put 500 28 n/a n/a n/a
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.