William Blair & Company’s Atea Pharmaceuticals AVIR Stock Holding History

William Blair & Company’s Portfolio AVIR Stock Details AVIR Fund Activity

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2026 Q1	$54K	Buy	+10,037	New	+$46.1K	﹤0.01%	1690
2023 Q4	–	Sell	-10,444	Closed	-$31.3K	–	1790
2023 Q3	$31.3K	Sell	10,444 -5	-0%	-$17	﹤0.01%	1635
2023 Q2	$39.1K	Sell	10,449 -5	-0%	-$19	﹤0.01%	1624
2023 Q1	$35K	Sell	10,454 -4	-0%	-$16	﹤0.01%	1629
2022 Q4	$50.3K	Buy	+10,458	New	+$52.9K	﹤0.01%	1574
2022 Q3	–	Sell	-14,439	Closed	-$103K	–	1821
2022 Q2	$103K	Buy	+14,439	New	+$98.6K	﹤0.01%	1538
2022 Q1	–	Sell	-28,869	Closed	-$258K	–	1911
2021 Q4	$258K	Sell	28,869 -53,944	-65%	-$841K	﹤0.01%	1475
2021 Q3	$2.9M	Buy	82,813 +57,395	+226%	+$1.59M	0.01%	603
2021 Q2	$546K	Buy	25,418 +16,438	+183%	+$494K	﹤0.01%	1123
2021 Q1	$555K	Buy	8,980 +3,650	+68%	+$247K	﹤0.01%	1082
2020 Q4	$223K	Buy	+5,330	New	+$172K	﹤0.01%	1384

Other funds holding AVIR

Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return

BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return

BCM

BML Capital Management Zionsville, Indiana $156M AUM 129.82% 1-Year Est. Return

TCM

Tang Capital Management San Diego, California $1.97B AUM 125.1% 1-Year Est. Return

VCM

Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM

BCLSI

Bain Capital Life Sciences Investors Boston, Massachusetts $1.11B AUM 171.34% 1-Year Est. Return

Two Sigma Investments New York $124B AUM 33.93% 1-Year Est. Return

Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return

State Street Boston, Massachusetts $2.9T AUM 29.55% 1-Year Est. Return

Acadian Asset Management Boston, Massachusetts $70.5B AUM 36% 1-Year Est. Return

William Blair & Company's AVIR Position: Q1 2026 in Review

William Blair & Company opened a new position in Atea Pharmaceuticals (AVIR) in Q1 2026: 10,037 shares worth $54K. The stake represents ﹤0.01% of the portfolio and ranks #1690 among its holdings. This is a return to the name: William Blair & Company previously reported a position in AVIR as recently as Q3 2023.

William Blair & Company first reported a position in AVIR in Q4 2020 and has held it in 11 quarters since. The position peaked at $2.9M in Q3 2021. 127 funds tracked by Wall St. Rank hold AVIR as of Q1 2026.

William Blair & Company held 10,037 shares of Atea Pharmaceuticals worth $54K as of Q1 2026.
Atea Pharmaceuticals was a new William Blair & Company position in Q1 2026.
Atea Pharmaceuticals made up ﹤0.01% of William Blair & Company's portfolio in Q1 2026, its #1690 holding.
William Blair & Company first reported a position in Atea Pharmaceuticals in Q4 2020 and has held it in 11 quarters since.
William Blair & Company's Atea Pharmaceuticals position peaked at $2.9M in Q3 2021.
127 funds tracked by Wall St. Rank held Atea Pharmaceuticals as of Q1 2026.

Based on William Blair & Company's 13F filing for Q1 2026, filed 8 May 2026.