Previous L2 studies used binary Truth-Value-Judgment (TVJ) tasks to investigate L1–L2 differences in scalar implicature derivation (some X implicates some but not all X). They examined participants’ judgments of sentences with weak scalar expressions (“Timothy ate some of the pretzels”) when stronger ones are true (“Timothy ate all of the pretzels”). Some studies indicate adult L2 learners are less likely than L1 users to accept such statements while others found the opposite, concluding that implicature derivation is “costly” for L2 learners, rendering them less pragmatically competent than L1 users. Importantly, related L1 research suggests that TVJ tasks only capture sensitivity to under-informativeness. This sensitivity might be completely overridden by metalinguistic attitudes in binary tasks, whereas graded tasks reveal nuanced judgment patterns. Exploring L2 response behaviors, we tested English L1 speakers and competent German L2 English learners using binary and graded tasks. In both tasks, we found evidence of pragmatic responding with no evidence of differences between groups. Bayes factor analyses of the graded data favored H0 over the hypotheses that L2 learners provide fewer or more rejections to under-informative input than L1 learners. We explore implications for L2 learners’ pragmatic abilities, differences with previous studies, and the role of TVJ tasks in under-informative contexts.