Courtesy of PCAOBNinety-three percent of special purpose acquisition companies were audited by firms outside of the six largest firms at the time of their initial public offering, according to the Public Company Accounting Oversight Board. The PCAOB found that between January 2015 and August 2025, 1,291 SPACs listed via IPO on U.S. exchanges. Only 7% of those SPACs were audited by the six large global network firms, and two non-affiliated firms together provided audits for more than 75% of SPACs at their IPO. SPAC IPO activity boomed in 2020 to 2021 during the pandemic, with 87% based in the U.S. (769 U.S. and 92 non-U.S.). In 2022, SPAC IPOs fell to 87 and have remained relatively stable since, with 84 SPACs so far this year.