A law firm previously hired by an investment bank to perform due diligence for a company’s initial public offering has no fiduciary duty preventing it from later suing that company, a divided Manhattan appellate court has ruled.

Epstein, Becker & Green had been disqualified last year from representing health-plan provider HF Management in an employment suit against a competitor, WellCare Health Plans Inc., which allegedly hired away two HF sales associates in violation of their employment agreements.