35 funds reported a position in Rapid Micro Biosystems, Inc. in their 13F for the quarter ended 30 June 2026, together 18.1 million shares worth $31.3 million. Against the quarter before, 5 opened a position, 9 added, 12 trimmed and 16 sold out; together they bought a net 1.7 million shares. The largest holders: Bain Capital Life Sciences Investors, LLC, Armistice Capital, LLC and ABG-WTT Global Life Science Capital Partners GP Ltd.
Funds holding35-12 on Q1 2026
Shares they held18.1Mworth $31.3 million
Net bought on the quarter1.7M sharesabout $2.9 million at the funds' values
Funds buying to selling14 to 28opened or added, to cut or sold
Opened 5Added 9Held 9Trimmed 12Sold out 16
What each fund did in RPID against its 13F for the quarter before; a change under 0.1% of a holding counts as held
Funds reporting a position in RPID in their 13F, each quarter; hover a bar for the shares they held
Filed so far for the quarter to 30 September 2026
3,405 funds have filed their 13F for the quarter so far; the rest are due by 16 November 2026. Of those, 6 reported a position in Rapid Micro Biosystems, Inc.: 3 opened one, 1 added, 1 trimmed and 1 sold out, a net 280,689 shares sold.
The largest moves in the name among the funds that have filed, against each fund's previous 13F.
The well-known funds
Of the 44 funds followed here, 4 reported a position in Rapid Micro Biosystems, Inc. in a 13F for the quarter ended 30 June 2026. The largest: Millennium Management, 236,599 shares worth $409,316, 0.0% of its reported book. New this quarter: Citadel Advisors. In the quarter, 2 funds added or opened a position and 2 trimmed or sold out; together they bought a net 35,809 shares, about $61,950 at the funds' own value per share on 30 June 2026. A change under 0.1% of a holding counts as held.
Value is what the fund reported. Read moreChange is shares against the fund's previous 13F; a fund with one filing read shows no change. 13Fs cover long US positions of managers above $100 million and are filed up to 45 days after the quarter.
The 50 largest of the 35 funds that reported a position in RPID in their 13F for the quarter ended 30 June 2026, by the value each reported. Read moreShare of all is the fund's part of all the shares the funds reported. Change is shares against the fund's 13F for the quarter before. A 13F lists a manager's long positions in US-listed shares at the quarter's end. What is a 13F?
Schedule 13D and 13G filed on the name, last twelve months
Filed
Schedule
Who
Holding
Of the class
Event date
Rule or purpose
Filing
14 August 2026
13G/A
Bain Capital Life Sciences Fund, L.P. and 3 others
A Schedule 13D is filed by anyone who crosses 5% of a class with intent to influence; a 13G by a passive holder. Read moreAmendments (/A) report a change, including an exit to zero. Holding and percentage are as the filer stated them on the cover page; the purpose is the filer's own words, cut short. 13D and 13G
Shares that failed to deliver at settlement, per day, from the SEC's half-month files, which arrive about two weeks after the period. Read moreLargest in the window: 61,313 on 18 August 2026. A fail is an operational fact about settlement, not a position.