SC Filed 2021-02-16 Event — SEC 0001839882-21-002172 →

Atlas Venture Fund X, L.P. → Spero Therapeutics, Inc. SPRO

Stake: — Shares: —

Composite Decision Signal · PASS (LOW BASE-RATE EDGE) Conviction Score: 10/100

Passive Schedule 13G filer baseline
Held by 1 tracked 13F institutional manager

Item 4 — Purpose of Transaction

Not extracted from this filing — typically because it's an amendment (13D/A) and Item 4 is unchanged from the parent filing. Read the raw SEC filing →

Cross-References

Insider Activity (last 365d)

8 transactions

8 buys · 0 sales · 0 awards/exercises

Issuer Cluster

6 13D/G filings on this issuer

5 other filings besides this one

Filer Track Record

4 filings by this filer

3 other filings in the data moat

Short Interest · settle 2026-10-15

DTC 1.51

840,529 shares short · +5.8% vs prior

Institutional Consensus · 2025-12-31

Held by elite portfolio managers

1 holder · $102K

Point72 Asset Mgmt

Form 4 Insider Transactions · last 365d

Date	Insider	Role	Type	Shares	Price	Value
2026-06-23	Deshpande Milind	director	Award	10,000	—	—
2026-06-23	Deshpande Milind	director	Award	20,000	$2.15	$43K
2026-06-23	Tregoning Kathleen	director	Award	10,000	—	—
2026-06-23	Tregoning Kathleen	director	Award	20,000	$2.15	$43K
2026-06-23	Smith Cynthia	director	Award	10,000	—	—
2026-06-23	Smith Cynthia	director	Award	20,000	$2.15	$43K
2026-06-23	VINK PATRICK V.J.J.	director	Award	10,000	—	—
2026-06-23	VINK PATRICK V.J.J.	director	Award	20,000	$2.15	$43K

Other 13D/G Filings on Spero Therapeutics, Inc.

Filed	Form	Filer	Stake	Shares
2022-11-14	SC	GSK PLC	—	—	view →
2021-09-16	SC	GLAXOSMITHKLINE PLC	—	—	view →
2020-12-07	SC	GLAXOSMITHKLINE PLC	—	—	view →
2020-06-04	SC	GLAXOSMITHKLINE PLC	—	—	view →
2018-07-17	SC	GLAXOSMITHKLINE PLC	—	—	view →

Other Filings by Atlas Venture Fund X, L.P.

Filed	Form	Issuer	Stake	Shares
2026-05-28	SCHEDULE 13D/A	Q32 Bio Inc. QTTB	3.60%	864,261	view →
2022-12-06	SC	Replimune Group, Inc. REPL	—	—	view →
2020-07-07	SC	Replimune Group, Inc. REPL	—	—	view →

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