SCHEDULE 13G/A

Acumen Pharmaceuticals, Inc.

Common stock, par value $0.0001 per share · CUSIP: 00509G209

Event date: 2025-09-30

Reporting persons may disclose overlapping interests. Their amounts are shown individually and are not added into a filing total.

Filing-level shares

Unavailable

Percent of class

Unavailable

• Franklin Resources, Inc.

  Shares: 2,305,096.00 · Class: 3.8%

• Charles B. Johnson

  Shares: 0.00 · Class: 0%

• Rupert H. Johnson, Jr.

  Shares: 0.00 · Class: 0%

Amounts are as disclosed in this filing. Schedule type alone does not establish investment intent.