Pfizer Inc.
CL ˙ SNSE ˙ US7170811035
SecurityCL:PFE / Pfizer Inc.
InstitutionKlingenstein Fields & Co Lp
Latest Disclosed Ownership9,547 shares
Latest Disclosed Value $ 268,080
Klingenstein Fields & Co Lp ownership in PFE / Pfizer Inc.

On May 12, 2026 - Klingenstein Fields & Co Lp filed a 13F-HR form disclosing ownership of 9,547 shares of Pfizer Inc. (CL:PFE) valued at $268,080 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 9,547 shares of Pfizer Inc.. This represents a change in shares of 0.00% during the quarter.

Klingenstein Fields & Co Lp has a history of taking positions in derivatives of the underlying security (PFE) in the form of stock options.

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.

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Institutional Put/Call Ratios
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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.

CL:PFE / Pfizer 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)
2026-05-12 2026-03-31 13F PFIZER COMMON 717081103 9,547 0 0.00 268 13.08 0.0079
2026-02-13 2025-12-31 13F PFIZER COMMON 717081103 9,547 200 2.14 238 -0.42 0.0089
2025-11-14 2025-09-30 13F PFIZER COMMON 717081103 9,347 0 0.00 238 5.31 0.0090
2025-07-30 2025-06-30 13F PFIZER COM 717081103 9,347 -4,162 -30.81 227 -33.92 0.0090
2025-04-28 2025-03-31 13F PFIZER COM 717081103 13,509 0 0.00 342 -4.47 0.0146
2025-01-30 2024-12-31 13F PFIZER COM 717081103 13,509 -3,753 -21.74 358 -28.26 0.0144
2024-10-29 2024-09-30 13F PFIZER COM 717081103 17,262 -330,925 -95.04 500 -94.88 0.0199
2024-08-01 2024-06-30 13F PFIZER COM 717081103 348,187 -6,531 -1.84 9,742 -1.03 0.4036
2024-04-29 2024-03-31 13F PFIZER COM 717081103 354,718 32,578 10.11 9,843 6.14 0.4088
2024-02-01 2023-12-31 13F PFIZER COM 717081103 322,140 -9,340 -2.82 9,274 -15.65 0.4134
2023-10-27 2023-09-30 13F PFIZER COM 717081103 331,480 8,427 2.61 10,995 -7.21 0.5369
2023-08-01 2023-06-30 13F PFIZER COM 717081103 323,053 -5,095 -1.55 11,850 -11.50 0.5477
2023-04-28 2023-03-31 13F PFIZER COM 717081103 328,148 794 0.24 13,388 -20.18 0.6702
2023-02-02 2022-12-31 13F PFIZER COM 717081103 327,354 -7,487 -2.24 16,774 14.47 0.8708
2022-10-28 2022-09-30 13F PFIZER COM 717081103 334,841 21,446 6.84 14,653 -10.82 0.8058
2022-08-01 2022-06-30 13F PFIZER COM 717081103 313,395 1,905 0.61 16,431 1.89 0.8545
2022-04-27 2022-03-31 13F PFIZER COM 717081103 311,490 -3,926 -1.24 16,126 -13.42 0.6907
2022-01-31 2021-12-31 13F PFIZER COM 717081103 315,416 -728 -0.23 18,625 36.97 0.7485
2021-10-26 2021-09-30 13F PFIZER COM 717081103 316,144 -111,400 -26.06 13,598 -18.78 0.5800
2021-07-26 2021-06-30 13F PFIZER COM 717081103 427,544 13,984 3.38 16,743 11.75 0.6927
2021-04-29 2021-03-31 13F PFIZER COM 717081103 413,560 12,865 3.21 14,983 1.59 0.6774
2021-02-02 2020-12-31 13F PFIZER COM 717081103 400,695 9,891 2.53 14,749 2.83 0.6686
2020-10-30 2020-09-30 13F PFIZER COM 717081103 390,804 7,518 1.96 14,343 14.43 0.7161
2020-08-03 2020-06-30 13F PFIZER COM 717081103 383,286 11,555 3.11 12,534 3.30 0.6848
2020-05-07 2020-03-31 13F PFIZER COM 717081103 371,731 28,733 8.38 12,134 -9.70 0.7906
2020-02-04 2019-12-31 13F PFIZER COM 717081103 342,998 -11,325 -3.20 13,438 5.56 0.6761
2019-11-01 2019-09-30 13F PFIZER COM 717081103 354,323 2,808 0.80 12,730 -16.40 0.6721
2019-08-12 2019-06-30 13F PFIZER COM 717081103 351,515 12,012 3.54 15,228 5.61 0.7904
2019-04-29 2019-03-31 13F PFIZER COM 717081103 339,503 12,756 3.90 14,419 1.10 0.7747
2019-01-22 2018-12-31 13F Pfizer COM 717081103 326,747 5,539 1.72 14,262 0.75 0.6051
2018-11-01 2018-09-30 13F Pfizer COM 717081103 321,208 -9,277 -2.81 14,156 18.07 0.5071
2018-07-26 2018-06-30 13F Pfizer COM 717081103 330,485 4,973 1.53 11,990 3.79 0.4570
2018-05-01 2018-03-31 13F Pfizer COM 717081103 325,512 13,055 4.18 11,552 2.08 0.4418
2018-01-30 2017-12-31 13F Pfizer COM 717081103 312,457 2,209 0.71 11,317 2.18 0.4165
2017-11-01 2017-09-30 13F Pfizer COM 717081103 310,248 -4,574 -1.45 11,076 4.74 0.4262
2017-07-27 2017-06-30 13F Pfizer COM 717081103 314,822 12,570 4.16 10,575 2.27 0.4146
2017-05-01 2017-03-31 13F Pfizer COM 717081103 302,252 -1,457 -0.48 10,340 4.83 0.4198
2017-01-26 2016-12-31 13F Pfizer COM 717081103 303,709 12,616 4.33 9,864 0.05 0.4309
2016-11-02 2016-09-30 13F Pfizer COM 717081103 291,093 -56,889 -16.35 9,859 -19.53 0.4536
2016-08-01 2016-06-30 13F Pfizer COM 717081103 347,982 6,139 1.80 12,252 20.92 0.5726
2016-05-02 2016-03-31 13F Pfizer COM 717081103 341,843 41,319 13.75 10,132 4.44 0.5067
2016-02-01 2015-12-31 13F Pfizer COM 717081103 300,524 54,828 22.32 9,701 25.71 0.4809
2015-10-23 2015-09-30 13F Pfizer COM 717081103 245,696 -5,825 -2.32 7,717 -8.49 0.3819
2015-08-03 2015-06-30 13F Pfizer COM 717081103 251,521 -9,850 -3.77 8,433 -7.26 0.3766
2015-05-05 2015-03-31 13F Pfizer COM 717081103 261,371 261,371 0.00 9,093 0.4026
2015-02-04 2014-12-31 13F Pfizer COM 717081103 0 -232,627 -100.00 0 -100.00
2014-10-21 2014-09-30 13F Pfizer COM 717081103 232,627 -6,225 -2.61 6,879 -2.96 0.3000
2014-07-24 2014-06-30 13F Pfizer COM 717081103 238,852 -4,648 -1.91 7,089 -9.36 0.3013
2014-05-02 2014-03-31 13F Pfizer COM 717081103 243,500 -144,914 -37.31 7,821 -34.26 0.3509
2014-02-05 2013-12-31 13F Pfizer COM 717081103 388,414 -4,661 -1.19 11,897 5.37 0.4256
2013-11-04 2013-09-30 13F Pfizer COM 717081103 393,075 -178,400 -31.22 11,291 -29.46 0.4420
2013-08-08 2013-06-30 13F Pfizer COM 717081103 571,475 571,475 16,007 0.5729
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
(%)
2019-11-01 2019-09-30 13F PFIZER COM Put 0 -100.00 0 n/a n/a n/a
2019-08-12 2019-06-30 13F PFIZER COM Put 600 0 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.