Renaissance Technologies's BIIB Position Overview
Renaissance Technologies (via Renaissance Technologies LLC) currently holds 964.4K shares of Biogen Inc. (BIIB) worth $135.09 M, representing 0.18% of the portfolio. First purchased in 2013-Q2, this long-term strategic position has been held for 50 quarters.
Based on 13F filings since 2013, Renaissance Technologies has maintained a long-term strategic position in BIIB, representing a significant commitment to this investment thesis. Largest addition occurred in Q3 2019, adding 1.7M shares. Largest reduction occurred in Q1 2021, reducing 1.1M shares.
Analysis based on 13F filings available since 2013 Q2
Renaissance Technologies's Biogen (BIIB) Holding Value Over Time
Track share changes against reported price movement
Quarterly Biogen (BIIB) Trades by Renaissance Technologies
| Period | Bought/Sold (Sh.) | % Change | Qtr. End Shares | Reported Price |
|---|---|---|---|---|
| Q2 2013 | +1.39 M | Add 0.00% | 1.39 M | $215.20 |
| Q3 2013 | -523,800 | Reduce 37.59% | 869,700 | $240.76 |
| Q4 2013 | -327,362 | Reduce 37.64% | 542,338 | $279.57 |
| Q1 2014 | -542,338 | Sold Out | 542,338 | $0.00 |
| Q2 2014 | +129,261 | New Buy | 129,261 | $315.31 |
| Q3 2014 | -36,600 | Reduce 28.31% | 92,661 | $330.81 |
| Q4 2014 | -27,500 | Reduce 29.68% | 65,161 | $339.45 |
| Q1 2015 | -34,861 | Reduce 53.50% | 30,300 | $422.24 |
| Q2 2015 | +74,961 | Add 247.40% | 105,261 | $403.94 |
| Q3 2015 | -70,300 | Reduce 66.79% | 34,961 | $291.81 |
| Q4 2015 | -34,961 | Sold Out | 34,961 | $0.00 |
| Q1 2016 | +127,661 | New Buy | 127,661 | $260.32 |
| Q2 2016 | -87,261 | Reduce 68.35% | 40,400 | $241.83 |
| Q3 2016 | +197,861 | Add 489.75% | 238,261 | $313.03 |
| Q4 2016 | +469,234 | Add 196.94% | 707,495 | $283.58 |
| Q1 2017 | +141,466 | Add 20.00% | 848,961 | $273.42 |
| Q2 2017 | -86,100 | Reduce 10.14% | 762,861 | $271.36 |
| Q3 2017 | -642,700 | Reduce 84.25% | 120,161 | $313.12 |
| Q4 2017 | -120,161 | Sold Out | 120,161 | $0.00 |
| Q1 2018 | +627,661 | New Buy | 627,661 | $273.82 |
| Q2 2018 | -306,161 | Reduce 48.78% | 321,500 | $290.24 |
| Q3 2018 | +524,575 | Add 163.16% | 846,075 | $353.31 |
| Q4 2018 | +168,639 | Add 19.93% | 1.01 M | $300.92 |
| Q1 2019 | +617,100 | Add 60.82% | 1.63 M | $236.38 |
| Q2 2019 | +851,263 | Add 52.17% | 2.48 M | $233.87 |
| Q3 2019 | +1.74 M | Add 70.00% | 4.22 M | $232.82 |
| Q4 2019 | +348,700 | Add 8.26% | 4.57 M | $296.73 |
| Q1 2020 | -95,994 | Reduce 2.10% | 4.47 M | $316.38 |
| Q2 2020 | -567,990 | Reduce 12.70% | 3.91 M | $267.55 |
| Q3 2020 | -88,961 | Reduce 2.28% | 3.82 M | $283.68 |
| Q4 2020 | -779,199 | Reduce 20.41% | 3.04 M | $244.86 |
| Q1 2021 | -1.1 M | Reduce 36.20% | 1.94 M | $279.75 |
| Q2 2021 | -608,159 | Reduce 31.38% | 1.33 M | $346.27 |
| Q3 2021 | -348,296 | Reduce 26.19% | 981,707 | $282.99 |
| Q4 2021 | +92,100 | Add 9.38% | 1.07 M | $239.92 |
| Q1 2022 | -29,600 | Reduce 2.76% | 1.04 M | $210.60 |
| Q2 2022 | +501,800 | Add 48.06% | 1.55 M | $203.94 |
| Q3 2022 | -391,500 | Reduce 25.32% | 1.15 M | $267.00 |
| Q4 2022 | -154,231 | Reduce 13.36% | 1 M | $0.28 |
| Q1 2023 | +263,561 | Add 26.35% | 1.26 M | $0.28 |
| Q2 2023 | -154,300 | Reduce 12.21% | 1.11 M | $0.28 |
| Q3 2023 | -23,140 | Reduce 2.09% | 1.09 M | $257.01 |
| Q4 2023 | -327,791 | Reduce 30.17% | 758,606 | $258.77 |
| Q1 2024 | +126,098 | Add 16.62% | 884,704 | $215.63 |
| Q2 2024 | -266,598 | Reduce 30.13% | 618,106 | $231.82 |
| Q3 2024 | +334,600 | Add 54.13% | 952,706 | $193.84 |
| Q4 2024 | +239,500 | Add 25.14% | 1.19 M | $152.92 |
| Q1 2025 | -387,700 | Reduce 32.52% | 804,506 | $136.84 |
| Q2 2025 | +240,600 | Add 29.91% | 1.05 M | $125.59 |
| Q3 2025 | -80,700 | Reduce 7.72% | 964,406 | $140.08 |
Renaissance Technologies's Biogen Investment FAQs
Renaissance Technologies first purchased Biogen Inc. (BIIB) in Q2 2013, acquiring 1,393,500 shares, as reported in their 13F filing for that period. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Renaissance Technologies has held Biogen Inc. (BIIB) for 50 quarters since Q2 2013. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Renaissance Technologies's largest addition to Biogen Inc. (BIIB) was in Q3 2019, adding 4,221,206 shares worth $982.78 M. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
According to the latest 13F filing for Q3 2025, Renaissance Technologies's firm, Renaissance Technologies LLC, owns 964,406 shares of Biogen Inc. (BIIB), valued at approximately $135.09 M. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
As of the Q3 2025 filing, Biogen Inc. (BIIB) represents approximately 0.18% of Renaissance Technologies's publicly disclosed stock portfolio, making it one of their key holdings. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Renaissance Technologies's peak holding in Biogen Inc. (BIIB) was 4,569,906 shares, as reported at the end of Q4 2019. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.