The Public Company Accounting Oversight Board’s (PCAOB) latest batch of 2021 audit inspection reports included a setback in results for Marcum largely related to the firm’s work dealing with special purpose acquisition companies (SPACs).

Of five firms inspected annually whose reports were published Monday, Marcum fared the worst, with 15 of its 25 audits reviewed recording deficiencies. The problem identified most frequently—11 times—was the firm’s insufficiency evaluating the appropriateness of an issuer’s accounting method or disclosure for one or more transactions or accounts.

Audit areas with frequent deficiencies included equity and equity-related transactions (nine) and revenue and related accounts (four).