Medifast, Inc.
MX ˙ BMV ˙ US58470H1014
SecurityMX:MED / Medifast, Inc.
InstitutionRenaissance Technologies Llc
ManagerJames Simons
Latest Disclosed Ownership773,710 shares
Ownership 6.96%
Renaissance Technologies Llc ownership in MED / Medifast, Inc.

2026-05-14 - Renaissance Technologies Llc has filed an SCHEDULE 13G/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 773,710 shares of Medifast, Inc. (MX:MED). This represents 6.96 percent ownership of the company. In their previous filing dated 2025-05-14 , Renaissance Technologies Llc had reported owning 888,928 shares, indicating a decrease of -12.96 percent.

Institutional Ownership: 13D/G Filings

This table shows a history of the 13D/G filings made by the investor and/or investor group. Note that the share values in this table are not directly comparable to any numbers shown in the 13F table (if any).

File
Date		Effective
Date		Form Prev
Shares		 Latest
Shares		 ΔShares
(Percent)		 Ownership
(Percent)		 ΔOwnership
(Percent)
2026-05-14 2026-05-14 13G/A 888,928 773,710 -12.96 6.96 -13.97
2025-05-14 2025-05-14 13G/A 1,006,210 888,928 -11.66 8.09 -12.07
2024-11-13 2024-11-13 13G/A 757,610 1,006,210 32.81 9.20 32.18
2024-02-13 2024-02-13 13G/A 632,110 757,610 19.85 6.96 20.42
2023-02-13 2023-02-13 13G/A 797,610 632,110 -20.75 5.78 -15.87
2022-02-11 2022-02-11 13G/A 1,010,510 797,610 -21.07 6.87 -20.02
2021-02-11 2021-02-11 13G/A 933,215 1,010,510 8.28 8.59 6.97
2020-02-13 2020-02-13 13G/A 990,000 933,215 -5.74 8.03 -2.90
2019-02-13 2019-02-13 13G/A 956,400 990,000 3.51 8.27 3.25
2018-02-14 2018-02-14 13G/A 951,500 956,400 0.51 8.01 -0.25
2017-02-14 2017-02-14 13G/A 746,300 951,500 27.50 8.03 26.46
2016-02-12 2016-02-12 13G 746,300 6.35

Important Note: One of the primary uses of the 13D/G filings is to evaluate the ability of a firm to control a company (ie, the "beneficial ownership"). To that end, firms are required to report not just direct holdings in companies, but indirect holdings that they control. For investment firms, these indirect holdings can include shares in funds they manage, advisory accounts, and in the case of activist campaigns, pledged votes. Therefore, share counts listed in 13D/G filings can differ significantly than share counts listed in 13F filings.

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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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 MEDIFAST COM 58470H101 773,710 -6,900 -0.88 7,884 -5.42 0.0123
2026-02-12 2025-12-31 13F MEDIFAST COM 58470H101 780,610 -20,300 -2.53 8,337 -23.86 0.0129
2025-11-13 2025-09-30 13F MEDIFAST COM 58470H101 800,910 -12,400 -1.52 10,948 -4.19 0.0145
2025-08-13 2025-06-30 13F MEDIFAST COM 58470H101 813,310 -75,618 -8.51 11,427 -4.63 0.0152
2025-05-14 2025-03-31 13F MEDIFAST COM 58470H101 888,928 -14,806 -1.64 11,983 -24.75 0.0181
2025-02-13 2024-12-31 13F MEDIFAST COM 58470H101 903,734 -102,476 -10.18 15,924 -17.32 0.0236
2024-11-13 2024-09-30 13F MEDIFAST COM 58470H101 1,006,210 47,600 4.97 19,259 -7.93 0.0290
2024-08-09 2024-06-30 13F MEDIFAST COM 58470H101 958,610 161,487 20.26 20,917 69,620.00 0.0355
2024-05-13 2024-03-31 13F MEDIFAST COM 58470H101 797,123 39,513 5.22 31 -40.00 0.0480
2024-02-13 2023-12-31 13F MEDIFAST COM 58470H101 757,610 3,400 0.45 51 -10.71 0.0788
2023-11-14 2023-09-30 13F MEDIFAST COM 58470H101 754,210 73,600 10.81 56 -9.68 0.0962
2023-08-11 2023-06-30 13F MEDIFAST COM 58470H101 680,610 29,600 4.55 63 -7.46 0.0904
2023-05-12 2023-03-31 13F MEDIFAST COM 58470H101 651,010 18,900 2.99 67 -6.94 0.0896
2023-02-13 2022-12-31 13F MEDIFAST COM 58470H101 632,110 -51,700 -7.56 73 -99.90 0.0998
2022-11-14 2022-09-30 13F MEDIFAST COM 58470H101 683,810 -76,600 -10.07 74,098 -46.02 0.1048
2022-08-12 2022-06-30 13F MEDIFAST COM 58470H101 760,410 -10,900 -1.41 137,262 4.20 0.1625
2022-05-13 2022-03-31 13F MEDIFAST COM 58470H101 771,310 -26,300 -3.30 131,724 -21.14 0.1546
2022-02-11 2021-12-31 13F MEDIFAST COM 58470H101 797,610 -43,300 -5.15 167,043 3.12 0.2078
2021-11-12 2021-09-30 13F MEDIFAST COM 58470H101 840,910 -54,300 -6.07 161,993 -36.05 0.2092
2021-08-13 2021-06-30 13F MEDIFAST COM 58470H101 895,210 800 0.09 253,327 33.71 0.3162
2021-05-13 2021-03-31 13F MEDIFAST COM 58470H101 894,410 -116,100 -11.49 189,454 -4.51 0.2357
2021-02-10 2020-12-31 13F MEDIFAST COM 58470H101 1,010,510 21,000 2.12 198,404 21.93 0.2154
2020-11-13 2020-09-30 13F MEDIFAST COM 58470H101 989,510 73,600 8.04 162,725 28.03 0.1625
2020-08-13 2020-06-30 13F MEDIFAST COM 58470H101 915,910 22,000 2.46 127,101 127.50 0.1097
2020-05-14 2020-03-31 13F MEDIFAST COM 58470H101 893,910 -39,305 -4.21 55,869 -45.37 0.0543
2020-02-13 2019-12-31 13F MEDIFAST COM 58470H101 933,215 10,600 1.15 102,262 6.96 0.0786
2019-11-13 2019-09-30 13F MEDIFAST COM 58470H101 922,615 232,300 33.65 95,611 7.95 0.0809
2019-08-12 2019-06-30 13F MEDIFAST COM 58470H101 690,315 -160,085 -18.82 88,567 -18.35 0.0780
2019-05-14 2019-03-31 13F MEDIFAST COM 58470H101 850,400 -139,600 -14.10 108,469 -12.36 0.0986
2019-02-12 2018-12-31 13F MEDIFAST COM 58470H101 990,000 31,600 3.30 123,770 -41.71 0.1355
2018-11-13 2018-09-30 13F MEDIFAST COM 58470H101 958,400 -34,666 -3.49 212,334 33.50 0.2183
2018-08-13 2018-06-30 13F/A-1 MEDIFAST COM 58470H101 993,066 466 0.05 159,049 71.47 0.1734
2018-08-13 2018-06-30 13F MEDIFAST COM 58470H101 992,600 92,758
2018-05-14 2018-03-31 13F MEDIFAST COM 58470H101 992,600 36,200 3.79 92,758 38.93 0.1014
2018-02-13 2017-12-31 13F MEDIFAST COM 58470H101 956,400 -700 -0.07 66,766 17.50 0.0736
2017-11-13 2017-09-30 13F MEDIFAST COM 58470H101 957,100 1,000 0.10 56,823 43.32 0.0669
2017-08-11 2017-06-30 13F MEDIFAST COM 58470H101 956,100 2,100 0.22 39,649 -6.33 0.0506
2017-05-12 2017-03-31 13F MEDIFAST COM 58470H101 954,000 2,500 0.26 42,329 6.86 0.0591
2017-02-13 2016-12-31 13F MEDIFAST COM 58470H101 951,500 4,300 0.45 39,611 10.66 0.0627
2016-11-14 2016-09-30 13F MEDIFAST COM 58470H101 947,200 -6,400 -0.67 35,795 12.83 0.0633
2016-08-12 2016-06-30 13F MEDIFAST COM 58470H101 953,600 125,700 15.18 31,726 26.93 0.0604
2016-05-13 2016-03-31 13F MEDIFAST COM 58470H101 827,900 81,600 10.93 24,994 10.24 0.0475
2016-02-11 2015-12-31 13F MEDIFAST COM 58470H101 746,300 157,800 26.81 22,673 43.44 0.0494
2015-11-12 2015-09-30 13F MEDIFAST COM 58470H101 588,500 43,575 8.00 15,807 -10.25 0.0377
2015-08-14 2015-06-30 13F MEDIFAST COM 58470H101 544,925 164,825 43.36 17,612 54.60 0.0401
2015-05-13 2015-03-31 13F MEDIFAST COM 58470H101 380,100 72,300 23.49 11,392 10.31 0.0243
2015-02-13 2014-12-31 13F MEDIFAST COM 58470H101 307,800 71,600 30.31 10,327 33.18 0.0249
2014-11-12 2014-09-30 13F MEDIFAST COM 58470H101 236,200 71,200 43.15 7,754 54.52 0.0212
2014-08-13 2014-06-30 13F MEDIFAST COM 58470H101 165,000 -95,684 -36.70 5,018 -33.83 0.0117
2014-05-14 2014-03-31 13F MEDIFAST COM 58470H101 260,684 -79,716 -23.42 7,583 -14.75 0.0182
2014-02-14 2013-12-31 13F MEDIFAST COM 58470H101 340,400 -37,300 -9.88 8,895 -12.42 0.0213
2013-11-13 2013-09-30 13F MEDIFAST COM 58470H101 377,700 21,700 6.10 10,156 10.74 0.0246
2013-08-12 2013-06-30 13F MEDIFAST COM 58470H101 356,000 356,000 9,171 0.0240
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.