Cliff Asness's BIIB Position Overview
Cliff Asness (via Aqr Capital Management LLC) currently holds 1.8M shares of Biogen Inc. (BIIB) worth $248.81 M, representing 0.16% of the portfolio. First purchased in 2012-Q4, this long-term strategic position has been held for 52 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 1.1M shares. Largest reduction occurred in Q4 2020, reducing 1.2M 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
| Period | Bought/Sold (Sh.) | % Change | Qtr. End Shares | Reported Price |
|---|---|---|---|---|
| Q4 2012 | +279,243 | Add 0.00% | 279,242 | $146.67 |
| Q2 2013 | +426,609 | Add 0.00% | 426,608 | $215.20 |
| Q3 2013 | -42,976 | Reduce 10.07% | 383,632 | $240.76 |
| Q4 2013 | +213,992 | Add 55.78% | 597,624 | $279.75 |
| Q1 2014 | +129,500 | Add 21.67% | 727,124 | $305.87 |
| Q2 2014 | +64,600 | Add 8.88% | 791,724 | $315.31 |
| Q3 2014 | +316,275 | Add 39.95% | 1.11 M | $330.81 |
| Q4 2014 | +93,290 | Add 8.42% | 1.2 M | $339.45 |
| Q1 2015 | -367,044 | Reduce 30.55% | 834,245 | $422.24 |
| Q2 2015 | +162,199 | Add 19.44% | 996,444 | $403.94 |
| Q3 2015 | -16,285 | Reduce 1.63% | 980,159 | $291.81 |
| Q4 2015 | -167,066 | Reduce 17.04% | 813,093 | $306.35 |
| Q1 2016 | -525,397 | Reduce 64.62% | 287,696 | $260.32 |
| Q2 2016 | +57,156 | Add 19.87% | 344,852 | $241.82 |
| Q3 2016 | +377,752 | Add 109.54% | 722,604 | $313.03 |
| Q4 2016 | -50,572 | Reduce 7.00% | 672,032 | $283.58 |
| Q1 2017 | +368,587 | Add 54.85% | 1.04 M | $273.42 |
| Q2 2017 | +264,040 | Add 25.37% | 1.3 M | $271.36 |
| Q3 2017 | +565,002 | Add 43.31% | 1.87 M | $313.12 |
| Q4 2017 | +96,473 | Add 5.16% | 1.97 M | $318.57 |
| Q1 2018 | +477,916 | Add 24.31% | 2.44 M | $273.82 |
| Q2 2018 | +396,445 | Add 16.22% | 2.84 M | $290.24 |
| Q3 2018 | +183,542 | Add 6.46% | 3.02 M | $353.31 |
| Q4 2018 | +132,044 | Add 4.37% | 3.16 M | $300.92 |
| Q1 2019 | +1.06 M | Add 33.71% | 4.22 M | $235.03 |
| Q2 2019 | -426,104 | Reduce 10.10% | 3.79 M | $233.87 |
| Q3 2019 | -277,141 | Reduce 7.31% | 3.52 M | $231.82 |
| Q4 2019 | -879,652 | Reduce 25.01% | 2.64 M | $296.18 |
| Q1 2020 | -516,832 | Reduce 19.60% | 2.12 M | $312.00 |
| Q2 2020 | +116,044 | Add 5.47% | 2.24 M | $260.74 |
| Q3 2020 | -19,186 | Reduce 0.86% | 2.22 M | $283.23 |
| Q4 2020 | -1.2 M | Reduce 54.11% | 1.02 M | $241.29 |
| Q1 2021 | +7,983 | Add 0.78% | 1.03 M | $276.72 |
| Q2 2021 | -510,943 | Reduce 49.83% | 514,462 | $345.16 |
| Q3 2021 | -163,602 | Reduce 31.80% | 350,860 | $282.99 |
| Q4 2021 | -22,639 | Reduce 6.45% | 328,221 | $239.92 |
| Q1 2022 | +68,085 | Add 20.74% | 396,306 | $210.60 |
| Q2 2022 | +116,900 | Add 29.50% | 513,206 | $201.61 |
| Q3 2022 | -258,748 | Reduce 50.42% | 254,458 | $258.65 |
| Q4 2022 | -56,640 | Reduce 22.26% | 197,818 | $274.77 |
| Q1 2023 | +224,668 | Add 113.57% | 422,486 | $276.96 |
| Q2 2023 | -86,098 | Reduce 20.38% | 336,388 | $284.35 |
| Q3 2023 | -29,709 | Reduce 8.83% | 306,679 | $257.01 |
| Q4 2023 | -269,539 | Reduce 87.89% | 37,140 | $258.77 |
| Q1 2024 | -30,778 | Reduce 82.87% | 6,362 | $215.43 |
| Q2 2024 | +17,195 | Add 270.28% | 23,557 | $231.82 |
| Q3 2024 | +26,324 | Add 111.75% | 49,881 | $192.91 |
| Q4 2024 | +489,811 | Add 981.96% | 539,692 | $151.78 |
| Q1 2025 | +829,150 | Add 153.63% | 1.37 M | $136.80 |
| Q2 2025 | -4,037 | Reduce 0.29% | 1.36 M | $125.59 |
| Q3 2025 | +418,776 | Add 30.68% | 1.78 M | $139.50 |
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 52 quarters since Q4 2012. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
Cliff Asness's largest addition to Biogen Inc. (BIIB) was in Q1 2019, adding 4,219,856 shares worth $991.79 M. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.
According to the latest 13F filing for Q3 2025, Cliff Asness's firm, Aqr Capital Management LLC, owns 1,783,581 shares of Biogen Inc. (BIIB), valued at approximately $248.81 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 0.16% of Cliff Asness'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.
Cliff Asness's peak holding in Biogen Inc. (BIIB) was 4,219,856 shares, as reported at the end of Q1 2019. Note: Analysis reflects filings available since Q2 2013; earlier records may be incomplete.