Common Stock, par value $0.001 per share

Acutus Medical, Inc.

2210 Faraday Ave., Carlsbad, CA, 92008

Deerfield Mgmt III Number of shares: 3,438,589 (comprised of shares of Common Stock and shares of Common Stock underlying Series A Common Equivalent Preferred Stock, in each case, held by Deerfield Private Design Fund III) Percentage of shares: 5.42%* Deerfield Private Design Fund III Number of shares: 3,438,589 Percentage of shares: 5.42%* Deerfield Mgmt Number of shares: 1,974,638 (comprised of shares of Common Stock and shares of Common Stock underlying Series A Common Equivalent Preferred Stock, in each case, held by Deerfield Partners) Percentage of shares: 4.90%* Deerfield Partners Number of shares: 1,974,638 Percentage of shares: 4.90%* Deerfield Management Number of shares: 5,492,725 (comprised of shares of Common Stock and shares of Common Stock underlying Series A Common Equivalent Preferred Stock, in each case, held by Deerfield Private Design Fund III and Deerfield Partners, together with shares of Common Stock underlying vested stock options and restricted share units held by Andrew ElBardissi for the benefit and at the direction of Deerfield Management) Percentage of shares: 9.10%* Flynn Number of shares: 5,492,725 (comprised of shares held by Deerfield Private Design Fund III and Deerfield Partners, together with shares and shares underlying vested stock options and restricted share units held by Andrew ElBardissi for the benefit and at the direction of Deerfield Management) Percentage of shares: 9.10%* *Percentage beneficial ownership reported herein reflects 29,912,305 shares of Common Stock outstanding as of November 8, 2024, as reported by the Company in its Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2024.

Deerfield Mgmt III Sole power to vote or direct the vote: 0 Shared power to vote or direct the vote: 3,438,589 Sole power to dispose or to direct the disposition: 0 Shared power to dispose or direct the disposition: 3,438,589 Deerfield Private Design Fund III Sole power to vote or direct the vote: 0 Shared power to vote or direct the vote: 3,438,589 Sole power to dispose or to direct the disposition: 0 Shared power to dispose or direct the disposition: 3,438,589 Deerfield Mgmt Sole power to vote or direct the vote: 0 Shared power to vote or direct the vote: 1,974,638 Sole power to dispose or to direct the disposition: 0 Shared power to dispose or direct the disposition: 1,974,638 Deerfield Partners Sole power to vote or direct the vote: 0 Shared power to vote or direct the vote: 1,974,638 Sole power to dispose or to direct the disposition: 0 Shared power to dispose or direct the disposition: 1,974,638 Deerfield Management Sole power to vote or direct the vote: 0 Shared power to vote or direct the vote: 5,492,725 Sole power to dispose or to direct the disposition: 0 Shared power to dispose or direct the disposition: 5,492,725 Flynn Sole power to vote or direct the vote: 0 Shared power to vote or direct the vote: 5,492,725 Sole power to dispose or to direct the disposition: 0 Shared power to dispose or direct the disposition: 5,492,725 Flynn is the managing member of the general partner of each of Deerfield Mgmt, Deerfield Mgmt III and Deerfield Management. Deerfield Mgmt III is the general partner of Deerfield Private Design Fund III and Deerfield Mgmt is the general partner of Deerfield Partners. Deerfield Management is the investment manager of the Deerfield Funds. Vested Stock options, restricted share units and shares of Common Stock held by Andrew ElBardissi, an employee of Deerfield Management and a director of the Company, are held for the benefit and at the direction of Deerfield Management.

Except as set forth in Items 4 and 6 of this Schedule 13D, no Reporting Person has effected any transactions in the Common Stock during the past 60 days.