Many firms engage in mimetic behavior to sustain or expand their market presence, adopting practices that may align with or deviate from those of original innovators, even if their products are similar. While existing studies often examine either product or practices imitation separately, the combined effects on sales performance are less understood. This gap is critical as firms need clear insights to leverage copies effectively and comprehend how different imitation strategies affect the sales performance of their “me-too” products. Drawing on social learning and product proliferation theories, this study analyzes approximately 2,550 product-year observations of imitations in the Brazilian pharmaceutical sector, some launched up to 52 years after the original innovation. The findings confirm performance heterogeneity among “me-too” copies, showing that product proliferation and portfolio diversity influence both overall proliferation and individual copy performance.