Cliff Asness's BIIB Position Overview
Cliff Asness (via Aqr Capital Management LLC) currently holds 1.53 M shares of Biogen Inc. (BIIB) worth $269.02 M, representing 0.14% of the portfolio. First purchased in 2012-Q4, this long-term strategic position has been held for 53 quarters.
Based on 13F filings since 2013, Cliff Asness has maintained a long-term strategic position in BIIB, representing a significant commitment to this investment thesis. Largest addition occurred in Q1 2019, adding 1.06 M shares. Largest reduction occurred in Q4 2020, reducing 1.2 M shares.
Analysis based on 13F filings available since 2013 Q2
Cliff Asness's Biogen (BIIB) Holding Value Over Time
Track share changes against reported price movement
Quarterly Biogen (BIIB) Trades by Cliff Asness
| Report Date | Bought/Sold (Sh.) | % Change | Qtr. End Shares | Reported Price |
|---|---|---|---|---|
| Q4 2025 | -254,965 | Reduce 14.30% | 1.53 M | $175.99 |
| Q3 2025 | +418,776 | Add 30.68% | 1.78 M | $139.50 |
| Q2 2025 | -4,037 | Reduce 0.29% | 1.36 M | $125.59 |
| Q1 2025 | +829,150 | Add 153.63% | 1.37 M | $136.80 |
| Q4 2024 | +489,811 | Add 981.96% | 539,692 | $151.78 |
| Q3 2024 | +26,324 | Add 111.75% | 49,881 | $192.91 |
| Q2 2024 | +17,195 | Add 270.28% | 23,557 | $231.82 |
| Q1 2024 | -30,778 | Reduce 82.87% | 6,362 | $215.43 |
| Q4 2023 | -269,539 | Reduce 87.89% | 37,140 | $258.77 |
| Q3 2023 | -29,709 | Reduce 8.83% | 306,679 | $257.01 |
| Q2 2023 | -86,098 | Reduce 20.38% | 336,388 | $284.35 |
| Q1 2023 | +224,668 | Add 113.57% | 422,486 | $276.96 |
| Q4 2022 | -56,640 | Reduce 22.26% | 197,818 | $274.77 |
| Q3 2022 | -258,748 | Reduce 50.42% | 254,458 | $258.65 |
| Q2 2022 | +116,900 | Add 29.50% | 513,206 | $201.61 |
| Q1 2022 | +68,085 | Add 20.74% | 396,306 | $210.60 |
| Q4 2021 | -22,639 | Reduce 6.45% | 328,221 | $239.92 |
| Q3 2021 | -163,602 | Reduce 31.80% | 350,860 | $282.99 |
| Q2 2021 | -510,943 | Reduce 49.83% | 514,462 | $345.16 |
| Q1 2021 | +7,983 | Add 0.78% | 1.03 M | $276.72 |
| Q4 2020 | -1.2 M | Reduce 54.11% | 1.02 M | $241.29 |
| Q3 2020 | -19,186 | Reduce 0.86% | 2.22 M | $283.23 |
| Q2 2020 | +116,044 | Add 5.47% | 2.24 M | $260.74 |
| Q1 2020 | -516,832 | Reduce 19.60% | 2.12 M | $312.00 |
| Q4 2019 | -879,652 | Reduce 25.01% | 2.64 M | $296.18 |
| Q3 2019 | -277,141 | Reduce 7.31% | 3.52 M | $231.82 |
| Q2 2019 | -426,104 | Reduce 10.10% | 3.79 M | $233.87 |
| Q1 2019 | +1.06 M | Add 33.71% | 4.22 M | $235.03 |
| Q4 2018 | +132,044 | Add 4.37% | 3.16 M | $300.92 |
| Q3 2018 | +183,542 | Add 6.46% | 3.02 M | $353.31 |
| Q2 2018 | +396,445 | Add 16.22% | 2.84 M | $290.24 |
| Q1 2018 | +477,916 | Add 24.31% | 2.44 M | $273.82 |
| Q4 2017 | +96,473 | Add 5.16% | 1.97 M | $318.57 |
| Q3 2017 | +565,002 | Add 43.31% | 1.87 M | $313.12 |
| Q2 2017 | +264,040 | Add 25.37% | 1.3 M | $271.36 |
| Q1 2017 | +368,587 | Add 54.85% | 1.04 M | $273.42 |
| Q4 2016 | -50,572 | Reduce 7.00% | 672,032 | $283.58 |
| Q3 2016 | +377,752 | Add 109.54% | 722,604 | $313.03 |
| Q2 2016 | +57,156 | Add 19.87% | 344,852 | $241.82 |
| Q1 2016 | -525,397 | Reduce 64.62% | 287,696 | $260.32 |
| Q4 2015 | -167,066 | Reduce 17.04% | 813,093 | $306.35 |
| Q3 2015 | -16,285 | Reduce 1.63% | 980,159 | $291.81 |
| Q2 2015 | +162,199 | Add 19.44% | 996,444 | $403.94 |
| Q1 2015 | -367,044 | Reduce 30.55% | 834,245 | $422.24 |
| Q4 2014 | +93,290 | Add 8.42% | 1.2 M | $339.45 |
| Q3 2014 | +316,275 | Add 39.95% | 1.11 M | $330.81 |
| Q2 2014 | +64,600 | Add 8.88% | 791,724 | $315.31 |
| Q1 2014 | +129,500 | Add 21.67% | 727,124 | $305.87 |
| Q4 2013 | +213,992 | Add 55.78% | 597,624 | $279.75 |
| Q3 2013 | -42,976 | Reduce 10.07% | 383,632 | $240.76 |
| Q2 2013 | +426,608 | Add 0.00% | 426,608 | $215.20 |
| Q4 2012 | +279,242 | Add 0.00% | 279,242 | $146.67 |
Cliff Asness's Biogen Investment FAQs
Cliff Asness first purchased Biogen Inc. (BIIB) in Q4 2012, acquiring 279,242 shares, as reported in their 13F filing for that period. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Cliff Asness has held Biogen Inc. (BIIB) for 53 quarters since Q4 2012.
Cliff Asness's largest addition to Biogen Inc. (BIIB) was in Q1 2019, adding 4,219,856 shares worth $991.79 M.
According to the latest 13F filing for Q4 2025, Cliff Asness's firm, Aqr Capital Management LLC, owns 1,528,616 shares of Biogen Inc. (BIIB), valued at approximately $269.02 M.
As of the Q4 2025 filing, Biogen Inc. (BIIB) represents approximately 0.14% of Cliff Asness's publicly disclosed stock portfolio, making it one of their key holdings.
Cliff Asness's peak holding in Biogen Inc. (BIIB) was 4,219,856 shares, as reported at the end of Q1 2019.