William Blair Investment Management’s Mirum Pharmaceuticals MIRM Stock Holding History

William Blair Investment Management’s Portfolio MIRM Stock Details MIRM Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q2	$164M	Buy	1,404,741 +1,069,072	+318%	+$107M	0.49%	59
2026 Q1	$31M	Sell	335,669 -1,032	-0.3%	-$97.1K	0.1%	185
2025 Q4	$26.6M	Buy	336,701 +23,442	+7%	+$1.68M	0.07%	228
2025 Q3	$23M	Buy	+313,259	New	+$19.9M	0.06%	276
2024 Q3	–	Sell	-677,939	Closed	-$23.2M	–	432
2024 Q2	$23.2M	Buy	677,939 +50,667	+8%	+$1.33M	0.06%	283
2024 Q1	$15.8M	Buy	627,272 +5,494	+0.9%	+$151K	0.04%	314
2023 Q4	$18.4M	Buy	621,778 +88,085	+17%	+$2.67M	0.05%	297
2023 Q3	$16.9M	Buy	533,693 +196,279	+58%	+$5.37M	0.06%	293
2023 Q2	$8.73M	Buy	+337,414	New	+$8.97M	0.03%	324

Other funds holding MIRM

FLSM

Frazier Life Sciences Management Palo Alto, California $4.59B AUM 237.58% 1-Year Est. Return

Jupiter Topco New York $245B AUM

BlackRock New York $6.73T AUM 46.02% 1-Year Est. Return

Fidelity Investments Boston, Massachusetts $2.3T AUM 54.33% 1-Year Est. Return

T. Rowe Price Associates Baltimore, Maryland $999B AUM 46.22% 1-Year Est. Return

Vanguard Portfolio Management Malvern, Pennsylvania $2.22T AUM

Vanguard Capital Management Malvern, Pennsylvania $4.68T AUM

State Street Boston, Massachusetts $3.38T AUM 44.17% 1-Year Est. Return

Geode Capital Management Boston, Massachusetts $1.88T AUM 44.46% 1-Year Est. Return

Invesco Atlanta, Georgia $1.26T AUM 61.52% 1-Year Est. Return

William Blair Investment Management's MIRM Position: Q2 2026 in Review

William Blair Investment Management increased its Mirum Pharmaceuticals (MIRM) stake by 318% in Q2 2026, buying an estimated $107M and bringing the position to 1,404,741 shares worth $164M. The position accounts for 0.49% of the portfolio, ranked #59.

William Blair Investment Management first reported a position in MIRM in Q2 2023 and has held it in 9 quarters since. 327 funds tracked by Wall St. Rank hold MIRM as of Q2 2026.

William Blair Investment Management held 1,404,741 shares of Mirum Pharmaceuticals worth $164M as of Q2 2026.
William Blair Investment Management bought 1,069,072 Mirum Pharmaceuticals shares in Q2 2026, an estimated $107M.
Mirum Pharmaceuticals made up 0.49% of William Blair Investment Management's portfolio in Q2 2026, its #59 holding.
William Blair Investment Management first reported a position in Mirum Pharmaceuticals in Q2 2023 and has held it in 9 quarters since.
327 funds tracked by Wall St. Rank held Mirum Pharmaceuticals as of Q2 2026.

Based on William Blair Investment Management's 13F filing for Q2 2026, filed 12 Aug 2026.