SEC 13F Intelligence

William Blair Investment Management, LLC / IM8N

William Blair Investment Management, LLC’s Insmed Inc Position

Does William Blair Investment Management, LLC own Insmed Inc (IM8N)? Yes902.7K shares worth $148M (+0.49% of its 13F portfolio) as of Q1 2026, down from 1.22M shares the prior filed quarter.

Position Value
$148M
Q1 2026
Shares
902.7K
% of Portfolio
+0.49%
Quarters Held
25
currently held

Position History IM8N

Reported value by quarter
Q1 ’20: $11MQ1 ’20Q2 ’20: $23MQ3 ’20: $77MQ4 ’20: $123MQ1 ’21: $128MQ1 ’21Q2 ’21: $143MQ3 ’21: $137MQ4 ’21: $134MQ1 ’22: $84MQ1 ’22Q2 ’22: $70MQ3 ’22: $77MQ4 ’22: $68MQ1 ’23: $63MQ1 ’23Q2 ’23: $90MQ3 ’23: $107MQ4 ’23: $132MQ1 ’24: $114MQ1 ’24Q2 ’24: $232MQ3 ’24: $177MQ4 ’24: $168MQ1 ’25: $176MQ1 ’25Q2 ’25: $168MQ3 ’25: $224MQ4 ’25: $213MQ1 ’26: $148MQ1 ’26filingsflow.com
QuarterSharesValue% of Portfolio
Q1 2026902.7K$148M+0.49%
Q4 20251.22M$213M+0.59%
Q3 20251.56M$224M+0.58%
Q2 20251.67M$168M+0.44%
Q1 20252.31M$176M+0.50%
Q4 20242.43M$168M+0.41%
Q3 20242.42M$177M+0.44%
Q2 20243.47M$232M+0.61%
Q1 20244.21M$114M+0.30%
Q4 20234.26M$132M+0.38%
Q3 20234.24M$107M+0.36%
Q2 20234.29M$90M+0.29%
Q1 20233.71M$63M+0.22%
Q4 20223.39M$68M+0.26%
Q3 20223.56M$77M+0.30%
Q2 20223.53M$70M+0.26%
Q1 20223.60M$84M+0.25%
Q4 20214.91M$134M+0.36%
Q3 20214.98M$137M+0.39%
Q2 20215.03M$143M+0.45%
Q1 20213.76M$128M+0.42%
Q4 20203.70M$123M+0.41%
Q3 20202.39M$77M+0.30%
Q2 2020819.4K$23M+0.09%
Q1 2020715.6K$11M+0.06%

Common-stock position only; options are excluded. Quarters where the fund filed no 13F or reported no position are absent. See William Blair Investment Management, LLC’s full portfolio or all institutional holders of IM8N.