Guardant Health, Inc.
US ˙ NasdaqGS ˙ US40131M1099

SecurityGH / Guardant Health, Inc.
InstitutionSimplex Trading, Llc
Latest Disclosed Ownership0 shares
Latest Disclosed Value $ 0
Simplex Trading, Llc ownership in GH / Guardant Health, Inc.

On May 14, 2026 - Simplex Trading, Llc filed a 13F-HR form disclosing ownership of 0 shares of Guardant Health, Inc. (US:GH) valued at $0 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 18,994 shares of Guardant Health, Inc.. This represents a change in shares of -100.00% during the quarter. The current value of the position is $0 USD.

Simplex Trading, Llc has a history of taking positions in derivatives of the underlying security (GH) in the form of stock options. The firm currently holds call options representing 14,300 of underlying shares valued at $1,320,891 USD and put options representing 19,600 of underlying shares valued at $1,810,452 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.

GH / Guardant Health, Inc. 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)
2026-05-14 2026-03-31 13F GUARDANT HEALTH COM 40131M109 0 -18,994 -100.00 0 -100.00
2026-02-11 2025-12-31 13F GUARDANT HEALTH COM 40131M109 18,994 18,994 1,940 0.0011
2025-05-12 2025-03-31 13F GUARDANT HEALTH COM 40131M109 0 -5,992 -100.00 0 0.0000
2025-02-11 2024-12-31 13F GUARDANT HEALTH COM 40131M109 5,992 5,992 0 0.0001
2024-07-25 2024-06-30 13F GUARDANT HEALTH COM 40131M109 0 -67,947 -100.00 0 -100.00
2024-04-25 2024-03-31 13F GUARDANT HEALTH COM 40131M109 67,947 42,756 169.73 1 0.0008
2024-02-02 2023-12-31 13F GUARDANT HEALTH COM 40131M109 25,191 10,218 68.24 1 0.0004
2023-11-01 2023-09-30 13F GUARDANT HEALTH COM 40131M109 14,973 14,973 0 0.0003
2023-08-04 2023-06-30 13F GUARDANT HEALTH COM 40131M109 0 -400 -100.00 0 0.0000
2023-04-27 2023-03-31 13F GUARDANT HEALTH COM 40131M109 400 -322 -44.60 0 0.0000
2023-02-02 2022-12-31 13F GUARDANT HEALTH COM 40131M109 722 -73,595 -99.03 0 -100.00 0.0000
2022-11-04 2022-09-30 13F GUARDANT HEALTH COM 40131M109 74,317 53,451 256.16 4,000 375.62 0.0045
2022-08-03 2022-06-30 13F GUARDANT HEALTH COM 40131M109 20,866 2,273 12.23 841 -31.68 0.0009
2022-05-02 2022-03-31 13F GUARDANT HEALTH COM 40131M109 18,593 16,072 637.52 1,231 388.49 0.0011
2022-02-23 2021-12-31 13F/A-1 GUARDANT HEALTH COM 40131M109 2,521 2,521 252 0.0003
2021-08-12 2021-06-30 13F GUARDANT HEALTH COM 40131M109 0 -12,601 -100.00 0 -100.00
2021-04-26 2021-03-31 13F GUARDANT HEALTH COM 40131M109 12,601 10,048 393.58 1,923 484.50 0.0035
2021-02-02 2020-12-31 13F GUARDANT HEALTH COM 40131M109 2,553 2,553 -79.74 329 -82.89 0.0004
2020-04-28 2020-03-31 13F GUARDANT HEALTH COM 40131M109 0 -11,504 -100.00 0 -100.00
2020-02-05 2019-12-31 13F GUARDANT HEALTH COM 40131M109 11,504 11,504 898 0.0020
2019-07-26 2019-06-30 13F GUARDANT HEALTH COM 40131M109 0 -1,856 -100.00 0 -100.00
2019-04-18 2019-03-31 13F GUARDANT HEALTH COM 40131M109 1,856 1,856 142 0.0004
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
(%)
2026-05-14 2026-03-31 13F GUARDANT HEALTH CALL Call 14,300 -47.62 1,321 -52.65 n/a n/a n/a
2026-02-11 2025-12-31 13F GUARDANT HEALTH CALL Call 27,300 -67.54 2,788 55,660.00 n/a n/a n/a
2025-11-12 2025-09-30 13F GUARDANT HEALTH CALL Call 84,100 -3.00 5 25.00 n/a n/a n/a
2025-08-05 2025-06-30 13F GUARDANT HEALTH CALL Call 86,700 -22.45 5 0.00 n/a n/a n/a
2025-05-12 2025-03-31 13F GUARDANT HEALTH CALL Call 111,800 16.46 5 100.00 n/a n/a n/a
2025-02-11 2024-12-31 13F GUARDANT HEALTH CALL Call 96,000 100.00 3 100.00 n/a n/a n/a
2024-11-08 2024-09-30 13F GUARDANT HEALTH CALL Call 48,000 -19.60 1 0.00 n/a n/a n/a
2024-07-25 2024-06-30 13F GUARDANT HEALTH CALL Call 59,700 -43.52 2 -50.00 n/a n/a n/a
2024-04-25 2024-03-31 13F GUARDANT HEALTH CALL Call 105,700 378.28 2 n/a n/a n/a
2024-02-02 2023-12-31 13F GUARDANT HEALTH CALL Call 22,100 -23.53 1 n/a n/a n/a
2023-11-01 2023-09-30 13F GUARDANT HEALTH CALL Call 28,900 -1.70 1 -100.00 n/a n/a n/a
2023-08-04 2023-06-30 13F GUARDANT HEALTH CALL Call 29,400 -72.11 1 -50.00 n/a n/a n/a
2023-04-27 2023-03-31 13F GUARDANT HEALTH CALL Call 105,400 -51.43 2 -60.00 n/a n/a n/a
2023-02-02 2022-12-31 13F GUARDANT HEALTH CALL Call 217,000 195.64 6 -99.87 n/a n/a n/a
2022-11-04 2022-09-30 13F GUARDANT HEALTH CALL Call 73,400 -37.74 3,951 -16.93 n/a n/a n/a
2022-08-03 2022-06-30 13F GUARDANT HEALTH CALL Call 117,900 107.57 4,756 26.42 n/a n/a n/a
2022-05-02 2022-03-31 13F GUARDANT HEALTH CALL Call 56,800 48.69 3,762 -1.52 n/a n/a n/a
2022-02-23 2021-12-31 13F/A GUARDANT HEALTH CALL Call 38,200 232.17 3,820 162.00 n/a n/a n/a
2022-02-04 2021-12-31 13F GUARDANT HEALTH CALL Call 11,500 1,458 n/a n/a n/a
2021-10-28 2021-09-30 13F GUARDANT HEALTH CALL Call 11,500 0.00 1,458 2.10 n/a n/a n/a
2021-08-12 2021-06-30 13F GUARDANT HEALTH CALL Call 11,500 19,727.59 1,428 61.36 n/a n/a n/a
2021-04-26 2021-03-31 13F GUARDANT HEALTH CALL Call 58 -67.42 885 -61.42 n/a n/a n/a
2021-02-02 2020-12-31 13F GUARDANT HEALTH CALL Call 178 -59.45 2,294 -53.25 n/a n/a n/a
2020-10-14 2020-09-30 13F GUARDANT HEALTH CALL Call 439 215.83 4,907 335.40 n/a n/a n/a
2020-07-13 2020-06-30 13F GUARDANT HEALTH CALL Call 139 -57.75 1,127 -50.76 n/a n/a n/a
2020-04-29 2020-03-31 13F GUARDANT HEALTH CALL Call 329 -6.80 2,289 -17.01 n/a n/a n/a
2020-02-05 2019-12-31 13F GUARDANT HEALTH CALL Call 353 40.64 2,758 72.16 n/a n/a n/a
2019-10-15 2019-09-30 13F GUARDANT HEALTH CALL Call 251 17.84 1,602 -12.84 n/a n/a n/a
2019-07-26 2019-06-30 13F GUARDANT HEALTH CALL Call 213 688.89 1,838 787.92 n/a n/a n/a
2019-04-18 2019-03-31 13F GUARDANT HEALTH CALL Call 27 207 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
(%)
2026-05-14 2026-03-31 13F GUARDANT HEALTH PUT Put 19,600 15.98 1,810 4.87 n/a n/a n/a
2026-02-11 2025-12-31 13F GUARDANT HEALTH PUT Put 16,900 -66.86 1,726 57,433.33 n/a n/a n/a
2025-11-12 2025-09-30 13F GUARDANT HEALTH PUT Put 51,000 -18.01 3 0.00 n/a n/a n/a
2025-08-05 2025-06-30 13F GUARDANT HEALTH PUT Put 62,200 -22.15 3 0.00 n/a n/a n/a
2025-05-12 2025-03-31 13F GUARDANT HEALTH PUT Put 79,900 97.28 3 200.00 n/a n/a n/a
2025-02-11 2024-12-31 13F GUARDANT HEALTH PUT Put 40,500 -23.30 1 0.00 n/a n/a n/a
2024-11-08 2024-09-30 13F GUARDANT HEALTH PUT Put 52,800 -46.45 1 -50.00 n/a n/a n/a
2024-07-25 2024-06-30 13F GUARDANT HEALTH PUT Put 98,600 -55.53 3 -50.00 n/a n/a n/a
2024-04-25 2024-03-31 13F GUARDANT HEALTH PUT Put 221,700 446.06 5 300.00 n/a n/a n/a
2024-02-02 2023-12-31 13F GUARDANT HEALTH PUT Put 40,600 36.70 1 n/a n/a n/a
2023-11-01 2023-09-30 13F GUARDANT HEALTH PUT Put 29,700 33.78 1 n/a n/a n/a
2023-08-04 2023-06-30 13F GUARDANT HEALTH PUT Put 22,200 -40.48 1 n/a n/a n/a
2023-04-27 2023-03-31 13F GUARDANT HEALTH PUT Put 37,300 -51.93 1 -100.00 n/a n/a n/a
2023-02-02 2022-12-31 13F GUARDANT HEALTH PUT Put 77,600 -19.83 2 -99.96 n/a n/a n/a
2022-11-04 2022-09-30 13F GUARDANT HEALTH PUT Put 96,800 97.55 5,210 163.66 n/a n/a n/a
2022-08-03 2022-06-30 13F GUARDANT HEALTH PUT Put 49,000 730.51 1,976 406.67 n/a n/a n/a
2022-05-02 2022-03-31 13F GUARDANT HEALTH PUT Put 5,900 -19.18 390 -46.58 n/a n/a n/a
2022-02-23 2021-12-31 13F/A GUARDANT HEALTH PUT Put 7,300 192.00 730 130.28 n/a n/a n/a
2022-02-04 2021-12-31 13F GUARDANT HEALTH PUT Put 2,500 317 n/a n/a n/a
2021-10-28 2021-09-30 13F GUARDANT HEALTH PUT Put 2,500 0.00 317 2.26 n/a n/a n/a
2021-08-12 2021-06-30 13F GUARDANT HEALTH PUT Put 2,500 7,252.94 310 -40.27 n/a n/a n/a
2021-04-26 2021-03-31 13F GUARDANT HEALTH PUT Put 34 -80.57 519 -76.98 n/a n/a n/a
2021-02-02 2020-12-31 13F GUARDANT HEALTH PUT Put 175 -66.60 2,255 -61.50 n/a n/a n/a
2020-10-14 2020-09-30 13F GUARDANT HEALTH PUT Put 524 141.47 5,857 232.78 n/a n/a n/a
2020-07-13 2020-06-30 13F GUARDANT HEALTH PUT Put 217 -34.24 1,760 -23.34 n/a n/a n/a
2020-04-29 2020-03-31 13F GUARDANT HEALTH PUT Put 330 -37.02 2,296 -43.92 n/a n/a n/a
2020-02-05 2019-12-31 13F GUARDANT HEALTH PUT Put 524 66.35 4,094 103.68 n/a n/a n/a
2019-10-15 2019-09-30 13F GUARDANT HEALTH PUT Put 315 -16.89 2,010 -38.55 n/a n/a n/a
2019-07-26 2019-06-30 13F GUARDANT HEALTH PUT Put 379 136.88 3,271 166.59 n/a n/a n/a
2019-04-18 2019-03-31 13F GUARDANT HEALTH PUT Put 160 1,227 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.