The investigation focuses on the company’s disclosures during the second and third quarters of 2025. In August, Portillo's reported that same-restaurant sales grew by a marginal 0.7%, while transaction volume fell by 1.4%. Despite maintaining an initial target of 12 new restaurant openings, the firm lowered its overall revenue and adjusted EBITDA growth expectations, signaling early signs of operational strain.

The situation intensified on September 10, when the company announced a strategic reset. Portillo's slashed its annual unit-growth target from 12 to 8 new locations and downgraded its same-restaurant sales outlook from a projected gain of up to 3% to an anticipated decline of 1.5%. Johnson Fistel is now reviewing these developments to determine if the company violated federal securities laws or breached fiduciary duties, potentially leaving shareholders with recoverable losses.