Flagship Pioneering’s Seres Therapeutics MCRB Stock Holding History
Bought
Maintained
Sold
| Quarter | Market Value | Status | Shares |
Change in Stake | Trade Value | Portfolio Weight | Portfolio Position | |
|---|---|---|---|---|---|---|---|---|
|
2026
Q2 | $9.12M | Hold |
1,155,850
| – | – | 0.59% | 5 |
|
|
2026
Q1 | $10.3M | Hold |
1,155,850
| – | – | 0.88% | 5 |
|
|
2025
Q4 | $17.2M | Hold |
1,155,850
| – | – | 5.32% | 4 |
|
|
2025
Q3 | $22.2M | Hold |
1,155,850
| – | – | 7.6% | 4 |
|
|
2025
Q2 | $12.8M | Sell |
1,155,850
-2
| -0% | -$18 | 4.78% | 4 |
|
|
2025
Q1 | $16.2M | Hold |
1,155,852
| – | – | 6.86% | 4 |
|
|
2024
Q4 | $19.3M | Hold |
1,155,852
| – | – | 5.76% | 5 |
|
|
2024
Q3 | $21.9M | Hold |
1,155,852
| – | – | 3.7% | 5 |
|
|
2024
Q2 | $16.7M | Hold |
1,155,852
| – | – | 1.98% | 5 |
|
|
2024
Q1 | $17.9M | Hold |
1,155,852
| – | – | 1.17% | 6 |
|
|
2023
Q4 | $32.4M | Hold |
1,155,852
| – | – | 2.45% | 6 |
|
|
2023
Q3 | $55M | Hold |
1,155,852
| – | – | 3.99% | 5 |
|
|
2023
Q2 | $111M | Hold |
1,155,852
| – | – | 4.94% | 4 |
|
|
2023
Q1 | $131M | Hold |
1,155,852
| – | – | 5.09% | 3 |
|
|
2022
Q4 | $129M | Hold |
1,155,852
| – | – | 4.13% | 4 |
|
|
2022
Q3 | $148M | Buy |
1,155,852
+436,912
| +61% | +$44.7M | 6.25% | 3 |
|
|
2022
Q2 | $49.3M | Hold |
718,940
| – | – | 1.86% | 7 |
|
|
2022
Q1 | $102M | Hold |
718,940
| – | – | 2.4% | 6 |
|
|
2021
Q4 | $120M | Hold |
718,940
| – | – | 1.85% | 7 |
|
|
2021
Q3 | $100M | Hold |
718,940
| – | – | 1.05% | 9 |
|
|
2021
Q2 | $343M | Sell |
718,940
-14,759
| -2% | -$6.23M | 4.38% | 4 |
|
|
2021
Q1 | $302M | Hold |
733,699
| – | – | 4.84% | 4 |
|
|
2020
Q4 | $360M | Sell |
733,699
-344,889
| -32% | -$202M | 6.54% | 3 |
|
|
2020
Q3 | $611M | Hold |
1,078,588
| – | – | 16.87% | 2 |
|
|
2020
Q2 | $103M | Hold |
1,078,588
| – | – | 2.98% | 6 |
|
|
2020
Q1 | $77M | Hold |
1,078,588
| – | – | 3.61% | 5 |
|
|
2019
Q4 | $74.4M | Hold |
1,078,588
| – | – | 4.16% | 5 |
|
|
2019
Q3 | $86.5M | Hold |
1,078,588
| – | – | 4.73% | 6 |
|
|
2019
Q2 | $69.5M | Buy |
1,078,588
+444,444
| +70% | +$42.2M | 3.01% | 8 |
|
|
2019
Q1 | $87.1M | Hold |
634,144
| – | – | 3.3% | 6 |
|
|
2018
Q4 | $57.3M | Hold |
634,144
| – | – | 2.8% | 5 |
|
|
2018
Q3 | $96.3M | Hold |
634,144
| – | – | 6.36% | 4 |
|
|
2018
Q2 | $109M | Hold |
634,144
| – | – | 20.89% | 3 |
|
|
2018
Q1 | $93.1M | Hold |
634,144
| – | – | 26.99% | 2 |
|
|
2017
Q4 | $129M | Hold |
634,144
| – | – | 32.61% | 2 |
|
|
2017
Q3 | $203M | Hold |
634,144
| – | – | 68.04% | 1 |
|
|
2017
Q2 | $143M | Hold |
634,144
| – | – | 50.54% | 1 |
|
|
2017
Q1 | $143M | Hold |
634,144
| – | – | 37.99% | 1 |
|
|
2016
Q4 | $126M | Hold |
634,144
| – | – | 40.85% | 1 |
|
|
2016
Q3 | $156M | Buy |
+634,144
| New | +$223M | 42.59% | 1 |
|
Other funds holding MCRB
LPC
Flagship Pioneering's MCRB Position: Q2 2026 in Review
Flagship Pioneering held its Seres Therapeutics (MCRB) position steady in Q2 2026 at 1,155,850 shares worth $9.12M. The position accounts for 0.59% of the portfolio, ranked #5.
Flagship Pioneering first reported a position in MCRB in Q3 2016 and has held it in 40 quarters since. The position peaked at $611M in Q3 2020. 36 funds tracked by Wall St. Rank hold MCRB as of Q2 2026.
- Flagship Pioneering held 1,155,850 shares of Seres Therapeutics worth $9.12M as of Q2 2026.
- Flagship Pioneering left its Seres Therapeutics share count unchanged in Q2 2026.
- Seres Therapeutics made up 0.59% of Flagship Pioneering's portfolio in Q2 2026, its #5 holding.
- Flagship Pioneering first reported a position in Seres Therapeutics in Q3 2016 and has held it in 40 quarters since.
- Flagship Pioneering's Seres Therapeutics position peaked at $611M in Q3 2020.
- 36 funds tracked by Wall St. Rank held Seres Therapeutics as of Q2 2026.
Based on Flagship Pioneering's 13F filing for Q2 2026, filed 14 Aug 2026.